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Conch. Icon. pi. 5. f. 17.

Hob. ?

This is another species founded on a single specimen of some-
what doubtful specific character.



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Geographical Distribution of the Terebratute. 1 77

21. Terebratula {Terebratella) suffusa, Reeve, Conch. Icon. pi. 5.
f. 18.

Hab. ?

A third doubtful species, partaking of the general typical
character of T. MaffeUanica, but equaUy distinguished by details
of form, sculpture, and colour which seem peculiar to it.

22. Terebratula (Terebratella) cruenta, DiUwyn, Syn. p. 295 ;
Conch. Icon. pi. 5. f. 20 a, b,

Terebratella cruenta^ Gray.

Terebratula sanguinea. Leach, Quoy (not of Chemnitz).

rubra, Sow. (not of Pallas).

Zelandica, Deshayes.

Terebratella Zelandica, Davidson, Suess.

Hab. New Zealand (dredged in Cook's Straits at a depth of
15 fathoms).

This beautiful and well-known species was described half a
century ago by Dillwyn, and admirably figured about the same
time by Leach in his ' Zoological Miscellany.'

23. Terebratula {Terebratella) rubella, Sowerby, Thes. Conch, i.
p. 850, pi. 69. f. 40-42 ; Conch. Icon. pi. 7. f. 26 a, b.
Terebratella rubella, Davidson.

Hab. Bass's Straits, South Australia (dredged from a depth of
about 27 fathoms) ; Calvert.

This species was thought at one time to be a variety of T.
{JValdheimia) picta; but it is uniformly of smaller size, and it
not only has the doubly-attached loop of Terebratella, but is
from a widely remote habitat. Japan (quoted by Professor Suess,
from Sowerby, for this species) is a wrong habitat.

24. Terebratula {Terebratella) rubicunda, Solander, Sowerby,
Thes. Conch, i. p. 851, pL 70. f. 45-47; Conch. Icon. pi. 7.
{.27a,b.

Terebratula incotispicua, Sowerby.

Hab. New Zealand.

This species occurs either of a purplish or deep coral-red
colour, or it is colourless. It has been dredged abundantly at
New Zealand ; but we have no record of the depth of its habitat.

25. Terebratula {Terebratella) Coreanica^ Adams and Reeve,
MoU. Voy. Samarang, p. 71, pi. 21. f. 8; Couch. Icon^ pi. 7.
f. 28a,A.

Hab. Corean Archipelago ; Belcher.

A delicate crimson-rayed species, of which many specimens



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178 Mr. L. Reeve on the Huiory, Synonymy ^ and

were dredged by Gapt. Beleber among the islands of the Corea.
Professor Suess describes an unpubhshed Terebratetta received
from Dr. Gk>uld with the habitat '^Hakodadi^' and name in
manuscript '' T. tniniata" Can it be our T. Coreanica ?

26. Terebrattda {Terebratella) sanytdnea, Chenmitz^ Conch. Cab.
viii. p. 96, pi. 78. f. 706 ; Conch. Icon. pL 7. f. 25 a, b, c.

Anomia sanguinea, Chemnits.
Terebratula sangmnea, Sowerby.

pulcheUa, Sowerby.

TerearateUa sangvinecLj Davidson.
Megerlia pulckella, Davidson.

Hab. Philippine and Sandwich Islands.

An examination of more than a dozen specimens of this
charming little species, most of them with the soft parts mace-
rated, so as to afford excellent comparisons of the loops, has
convinced me that Mr. Sowerb/s T. pulcheUa is merely a variety
of his T. sangumea {Anomia aangumea, Chemnitz), in which the
deltidium plates are forced asunder by circumstances in its mode
of attachment. The apophysis is the same in both forms,
differing somewhat from the typical form of the apophysis in
Terebratella, and partaking of that in MegerUa.

27. Terebratvla {Terebratella) Labradorensis, Sowerby, Thes.
Conch, i. p. 862, pi. 71. f. 89, 90; Conch. Icon. pL 5. f. 19,
TerebrateUa Labradorensis, Davidson.

Hab, Labrador; Goodsvr.

A rounded, opake-white, ribbed species, of rather small size.

28. Terebratula {Terebratella) Spitzberyensis, Davidson, Proc
Zool. Soc. 1852, p. 78; Conch. Icon. pi. 7. f. 24

Hab. Spitzbergen.

7. Spitzberyensis is a small, narrowly-ovate species, smooth
and semipellucid like the large T. vitrea. Professor Suess
remarks that the figure of a species of Middendorf, which is
unknown to me {T. frontalis), is like it. Can they be one and
the same species ? But Professor Suess goes on to ask, is 71
frontalis the same as T. transversa} — which has no relation
whatever, as a comparison of our figures of that species in ' Conch.
Icon.^ with T. Spitzberyensis will show.

Subgenus 5. Maoas, Sowerby.

Apophysis a loop resembliny that of Terebratella, but contracted,
cmd having the cross piece broadly laminated next the central
septum,

29. Terebratula {Magas) Valenciennesii, Davidson, Annals and



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GtograpMcai Distribuium of the Terebratulse. 179

Mag. Nat, Hist. 1850, v. pi. 15. f. 1 ; Conch. Icon. pi. 8.
f. 31 a, b, c,

fVcUtonia Valenciennem, Davidson.
Terebratella Evansii, Davidson.
Magas Evansii, Gray.
Argiope Valenciennesii, Suess.

Hob. New Zealand.

Mr. Davidson generously yields to my suggestion that his
Waltonia Valenciennem and Terebratella Evansii are one and
the same; the loop has, however^ the contracted laminated
structure characteristic of Magas, and I agree with Dr. Gray in
assigning it to that genus. Professor Suess's assigning it to
Argiope is obviously a blunder. jSeveral specimens have come
under my notice, all of a bright orange-red colour.

80. Terebratula {Magas) cremdata, Sowerby, Thes. Conch, i.
p. 858, pi. 71. f. 96-98; Conch. Icon. pi. 8. f. 82.

Terebratella crenulata, Davidson.
Magas crentdata. Gray.

Hab. Santa Cruz, Canaries ; fide Cuming.

This species has somewhat the appearance of 7. [Terebratella)
Labradorensis, or of a young T. {Terebratella) Magellanica; but
it is convex, and ribbed in both valves, and it has distinctly the
contracted laminated apophysis of the preceding species. The
recorded habitat is peculiar, and, I fancy, a little doubtful.

Subgenus 6. Boucha&dia, Davidson.

Jpqpkgsis represented by a central septum, with the laminated
cross piece o/ Magas callously produced and thickened into the
form of an anchor.

31. Terebratula [Bouchardia) Cumingii, Davidson, Proc. Zool.
Soc. 1852, p. 78, pi. 14. f. 10-16; Conch. Icon. pi. 8.
f.29.

Terebratella? CumingU, Davidson.
Magas CunUngii, Gray.

Hob. New Zealand.

This very interesting species is in my opinion neither a
Terebratella nor a Magas. It begins to show internally the
eallons thickening both of the valves and of the apophysis of
Bouchardia tutipa, and is, above all, distinguished by the acumi-
nated beak and terminal foramen peculiar to that and to the
following species.



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180 Mr. L. Reeve on the History^ Synonymy, and

32. Terebratula {Bouchardia) fibula, Reeve, Conch, Icon. pi. 8.
f. 30 fl, 4.

Hob. Bass's Strait, South Australia; Calvert*
This remarkable shell is curiously intermediate in its characters
between T. (Bouchardia) Cumingii axid tul^a. The beak is more
acuminated than in the former ; and the area of the deltidium,
which in B. Cumingii and tulipa is excavately grooved, is in B.
fibula flat. In respect of the c»llous development of the interior,
it is about intermediate between the other two. Mr. Calvert, of
whom the B* fibula was purchased for the British Museum, re-
ports that he dredged it in Bass's Strait from a depth of 200
fathoms ; but Mr. Milligan, of Hobart Town, Secretary to the
Royal Society of Tasmania, now in London, informs me that
Bass's Strait, when sounded by Captain Stokes, was found not
to be deeper in any part than from 70 to 75 fathoms.

33. Terebratula (Bouchardia) tulipa, De Blainville, Diet Sci.
Nat. liii. f. 144.

Bouchardia tulipa, Gray.
Terebratula rosea, Humphreys, ined.
Bouchardia rosea, Davidson.
Pachyrhynchus roseus. King.
Terebratula unguis, Kiister.

Hab. Brazil (dredged at Rio Janeiro from a depth of about
10 to 13 fathoms) ; MacgUlivray.

71 (Bouchardia) Cumingii, fibula, and tulipa are distinguished
from all other Terebratula by the structure of the shell's beak,
which is acuminated and has the foramen at the extremity. The
deltidium plates are therefore dispensed with, and the length-
ened area which occupies their place is either flat, as in B. fibula,
or excavately grooved, as in B. Cuminffii and tulipa. Con-
comitant with this change in the structure of the beak there ia a
change in the interior of the shell. The apophysial skeleton,
retaining the cross piece of Magas, becomes solidiiSed and com-
paratively rudimentary, and callosities begin to be formed about
the hinge of B. Cumingii, until they assume in B. tulgni the
function of heavy interlocking plaits*

Subgenus 7. Megerlia, Kmg.
Apophysis a rather small loop on a pair of projecting blades
affixed by a laminated cross piece to a central septum, and on
either side by a short intermediate hbed process.

34. Terebratula (Megerlia) truncata, Linn. Syst. Nat. p. 1152;
Conch. Icon. pi. 11. f. 48 a, 4, c.

AnoffUa truncata, Linnaeus.
disculus, Pallas.



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Geographical Distribution of the Terebratulse. 181

Ter^atula truncata, Lamarck.

^culus, De Blainville.

Terebratella truncata, D*Orbigny.
Terebratula monstrosa, ScaccU.
Orthis truneata, Philippi.
MegerUa truneata, Kid^.
Ortkis oblita, Michelotti.
Megathyris oblita, D'Orbigny.

Hab. Mediterranean (affixed to corals at depths of from 60
to 100 fathoms). Cape Finisterre (at a depth of 90 fathoms).
Canaries.

Mr. Jeffreys possesses a specimen of this well-known species^
formerly belonging to Dr. Turton, which is said to have been
dredged in Torbay ; but its recorded British habitat has not been
confirmed by the discovery of any farther specimens.

Subgenus 8. Kbaussia^ Davidson.
Apophysis a central septum, Jrom the extremity of which diverge a

P^ir offan-like processes.
35. Terebratula (Kraussia) rubra, Pallas, Misc. Zool. pi. 14. f. 2-
11 ; Conch. Icon. pi. 9. f. 37 a, b, c.

AnonUa rubra, Pallas.

-»^ promontorii Bona Spei, Chemnitz.

Capensis, Gmelin.

Terebratula rubra, De Blainville.
— Capensis, Krauss.

Algoensis, Sowerby,

Kraussia rubra, Davidson.

Hob. South Africa.

This very interesting species, though admirably figured, with
its loopless bifurcating apophysis, nearly a century ago by Pallas,
and again a few years later by Chemnitz, was not known to
Valenciennes when preparing his monograph of the genus for
Lamarck's * Animaux sans Vertebres,* nor even to Sowerby when
publishing his monograph in the ' Thesaurus.' It is characterized
bv a remarkably short beak and largeforamen ; and the deltidium
plates are accordingly very widely separated. The colouring,
which is mainly on the radiating ribs, is bright coral-red. Mr.
Sowerby^B T. Algoensis, pronounced by Mr. Davidson to be a
Terebratella, and by Dr. Gray to be a Kraussia " scarcely dif-
fering from K. pisum,'' is founded on a bleached fragmentary
ventral valve, preserved in the British Museum, o{ Kraussia rubra.

86. Terebratula {Kraussia) cognata, Chemnitz, Conch. Cab. viii.
p. 78, pi. 76. f. 688 a, )8 ; Conch. Icon. pi. 9. f. 36 a, b.
Cognata Anomia craniolaris bast perforata, Chemnitz.
Hab. South Africa.
Kraussia cognata (of which a single specimen in Mr. Cuming's



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182 Mr. L. Reeve an the History, Synonymy, and

collection^ notwithstanding that the species was described and
figured by Chemnitz^ is the only one known to me) might readily
be taken for a worn mis-shapen specimen of K, rubra but for
one important character : the dorsal valve is conspicuously ser-
rated within the margin by a row of spinous teeth. No mention
is made of this character in the diagnosis of the British Museum
Catalogue; but it is figured and carefully described by Chem-
nitz — '^ margine interiori subtilissirae et acutissime denticulato/'

37. Terebraiula {Krausria) pisum, Valenciennes apud Lamk.
Anim. sans Vert. vii. p. 330; Conch. Icon. pi. 9. f.36 a, b.

Terebraiula Natalentis, Knmss.
Krcmssia ptsum, Davidwm.

Hab. South Africa.

This little species, which M. Valenciennes named ^' the pea/'
and likened to a cherry-stone, resembles K. Lamarckiana ; but it
is constantly distinguished by the fineness of the radiating ridges,
while it is of lai^r size.

38. Terebraiula (Kraussia) Deshayesii, Davidson, Proc. Zool. Soc.
1852, p. 80, pi. 14. f. 20, 21; Conch. Icon. pi. 9. f. 35 a, h.

Terebraiula Capensis, Adams and Reeve (not of Gmelin).
Kraussia Deshayesii, Davidson.

Hab. Cape of Gkx)d Hope (dredged from a depth of 120
fathoms); Belcher.

Very closely allied to K. pisum and Lamarckiana, but of
a more triangular form, and painted in a characteristic man-
ner with crimson rays. The habitat '^ Corea " given by Mr.
Davidson for this species, on the authority of Mr. Cuming,
is incorrect. Kraussia Deshayesii was dredged oflf the Cape of
Good Hope in the same vessel in which Terebratulina abyssicola
was dredged at Corea ; and the labels got confounded together.
Kraussia is as exclusively a type of the south temperate zone as
Terebratulina is of the north temperate.

39. Terebraiula (Kraussia) Lamarckiana, Davidson, Proc. Zool.
Soc. 1852, p. 80, pi. 14. f. 22, 23; Conch. Icon. pi. 9. f. 84.
TerebrateUa Lamarckiana, Davidson.

Hab. Sydney and New Zealand.

This little species is of a broadly ovate pouch-like form,
flexuous in growth and rather strongly wrinkled. It has the
bifurcated apophysis of Kraussia, but is a little removed from
the typical forms of the group, all of which are natives of South
Africa. The septum in this species is continued beyond the
point of bifurcation nearly to the margin, which is in both vaives
neatly spinulose.



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Geographicdl Distribution of the Terebratulse. 183

Subgenus 9. Gwynia ?, King.

Apophysis unknown.

40. Terebratvla {Gvoyma ?) capsula, Jefi&eys^ Ann. & Mag. Nat.
Hist. 1859, iii. pL 2. f. 7 a, A ; Conch. Icon. pi. 10. f. 39,

Tenbratmla etmsula, Jeffireys.
Gwpda capsulBf King.

Hob. Plymouth; iVbrmoTi. Belfast Lough jflymfoum. Etretat,
Nonnandy; Jeffreys.

Is this very minute form, it has been asked, an adult shell, or
the fry of Argiope cisteUubum or of some other Terebratula^
An Argiope it certainly is not ; and I am unable, after a most
tedious examination of specimens, to add anything to what is
known on the subject. Its history is as follows : — In the ' Annals
and Magazine of natural History ' for August 1858, Mr. Jeflfreys
announ^ that a very minute brachiopodous shell (^V^h of an
inch in length and ^\jth in breadth) had been found by Mr.
Norman (a well-known collector of British shells resident in
Durham) among some shell-sand received by him from Ply-
mouth. " Being so excessively smaU,^^ adds Mr. Jeffreys, " as
to defy any attempt to examine the internal structure without
injuring the specimen, it is impossible to say whether it is an
Argiope ; but having carefully compared it with A. cisteUula,
which varies greatly in form, I am inclined to consider it at pre-
sent an extreme variety of that species.^' Attention being
drawn to the subject, other specimens were dredged by Mr.
Hyndman in Belfast Lough (reported, however, to be Argiope
eisielhda), and by Mr. Jeffreys himself at Etretat, on the coast
of Normandy. After an examination of specimens under a
magnifying power of 100 diameters, Mr. Jeffreys came to the
conclusion that the shell was not an Argiope, but a form more
alUed to Terebratulina. Is it then the fry of T. caput-serpentis ?
Mr. Jeffreys thought not, because the valves are nearly equal,
and have no indication of the radiating dichotomous ridges of
that species. But what do we know of the Brachiopods in the
fry state 7 Is it at all likely that they bear the detailed charac-
teristics of the adult ? He described it in the following year
(Ann. and Mag. Nat. Hist. January 1859) simply as a Tere-
bratula, with the remark, ^' it may be a question whether it
ought not to be placed in a new subgenus.^' Prof. King, of
Quern's College, Galway, upon seeing this announcement, lost
no time in borrowing the specimens, and, in compliment to Mr.
(J. Gwyn) Jeffreys, created the genus Gwynia for its reception
(Proc. Dnbl. Umv. Zool. Assoc. April 1859). Prof. King says,
'' The principal generic character of Gwynia is in the labial ap-
penda^ being attached directly to the shell, and not to a loop.''



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184 Mr. L. Reeve an the History, Synonymy, and

The grounds for this conclusion appear to me to be very in-
sufficient. No loop^ it is true, has been observed ; but it is to
be remarked that the shell much more resembles that of the
free-looped Terebratula than that of the subgenera in which the
labial appendages rest more directly on the shell. The most re-
markable peculiarity of this shelly as compared with ordinary
adults^ is the prominence of the dorsal umbo. The shell is
almost double-beaked. Its internal structure is not yet under-
stood. " Woodward and myself/' writes Mr. Davidson to me,
in a letter just received, '' wast^ a whole day at the British
Museum (April 27th, 1859) in endeavouring to find some kind
of loop in T. aqmUa, but could find none, and thought it the
fry of some other species.^'

Subgenus 10. Mobrisia, Davidson.

Apophysis a short simple loop attached to a central process in the
form of a spur.

41. Terebratula {Morrisia) anomioides, Scacchi, Philippi, Enmn.
Moll. Sicil. ii. p. 69, pi. 18. f. 9 ; Conch. Icon. pi. 10. f. 40.

Orthis onomioides, Scacchi.
Terebratula appressa, Forbes.
Morrisia aiMmoides, Davidson.

Hab. Mediterranean (dredged in the ^gean from a depth of
95 fathoms) ; Forbes.

An ^nofnia-like form, in which the ventral valve is very little
beaked, and the foramen encroaches upon the dorsal valve,
occupying the place of the umbo; there is consequently no
deltidiunu

42. Terebratula {Morrisia) Davidsoni, Deslongchamps, Ann. and
Mag. Nat Hist. 1855, xvi. pi. 10. f. 20 a,b, c, d.

Hab. Mediterranean (dredged at Tunis, adhering to Caryo-
phyllia ramea) ; Deslongchamps.

I do not see that the differences alleged to exist between this
species and the preceding are clearly specific. Far greater dif-
ferences may be observed in bivalves of similar habit of which
specimens are more abundant, as of the common Anomia ephip-
pium for example, which it so closely resembles externally, though
minute and of a different organization. J^orrisiaDavidsoni is dis-
tinguished from M. anomiotdes,&o far as the few specimens known
permit of a distinction being noj;ed, by the following characters : —
The shell is larger and of a more transverse growth, with the
concentric lines of increase rising almost to the sharpness of
asperities. The foramen is large, and encroaches so much upon
the dorsal valve as to appear almost to belong to it alone ; and the



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Geographical Distribution of the Terebratobe. 185

dorsal valve is flat and irregularly indented^ denoting a dose
attachment to the body to which the pedicle is affixed.

43. TerebrattJa {Morrisia) luni/era, Philippic Enum. Moll. Sicil.
i. p. 97, pi. 6. f. 16 a-f.

Ortkis hmifera, Philippi.
Morritia lunifera. Gray.

Hab. Mediterranean ; Philippi.

A delicate hyaline species, of a more triangular form than
either of the preceding two, puckered with indentations at the
margin.

Subgenus 11. Argiofe, Deslongchamps.

Apophysis a loop sweeping round the valve on either side, supported
in front by from one to three short marginal septa,

4A. Terebrattda {Argiope) decoUqta, Chemnitz, Conch. Cab. viii.
p. 96, pi. 78. f. 705 a, b, c, d; Conch. Icon. pi. 10. f. 43 a, b.

Anomia decoUata, Chemnitz.

detruncata, Gmelin.

Terebratula decoUata, Deshayes,

detruncataf De Blainvme.

Megathyris detruncata, D'Orbigny.
Terebratula aperta, De Blainvifle.
— dimidiata, Scaccbi.

eardita, Risso.

uma-antiqua, Risso.

Orthis detruncata, Philippi.
Argiope detruncata, DesloDgchamps.
decollata, Davidson.

Hab. Mediterranean (affixed to corals at depths of from 50 to
100 fathoms).

The loop is in this well-known species supported in front by
three marginal septa.

45. Terebratula (Argiope) cuneata, Risso, Eur. Merid. pi. 4.
f. 179; Conch. Icon. pi. 10. f. 44.

Anomia Pera, Miihlfeldt.
Orthis Pera, Philippi.
Terebratula Soldaniana, Risso.
Argiope cuneata, Davidson.

Hab. Mediterranean (at depths of from 30 to 70 fathoms) ;
Canaries.

A narrower form than the preceding species, with the beak
more tumidly produced, and the hinge-area consequently less
abruptly truncated. The loop rests upon only one marginal
septum.

Ann. ^ Mag. N. Hist. Ser. 3. Vol. vii. 13



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186 Mr. L. Beeve on the Hitiory, Synonymy, and

46. Terebraiula (Argiope) NeapoUiana, Scacchi, Oss. Zool. ii.
p. 18; Conch. Icon. pi. 10. f. 45.

Terebraiula seminulum, Philippi.
" Orthis NeapoUtana, Philippi.
Argiope Neaji>olitana, DayidBon.
Forbesti, Davidson.

Hab, Mediterranean (at depths of from 60 to 100 fathoms) ;
Canaries.

Of a more triangular form than the preceding species^ while
the valves are plicately indented at the margin in rather a cha-
racteristic manner, the radiating ribs being arranged in three
fasciculi, or as it were on three shields. The apophysis is the
same as in A. cuneata ; but the margin of the valve is more
thickened internally, and between it and the loop there is a
distinct row of spinous teeth.

47. Terebraiula {Argiope) cisteUula, Searles Wood, Ann. and
* Mag. Nat. Hist. vi. p. 253 (fossil); Conch.Icon.pl. 10. f.46.

Megaihyris cisiellula, Forbes and Hanley.
Argiope cisteUula, Davidson.

Hab. Mediterranean and British Seas.

This little species, originally discovered by Mr. Searles Wood
in a fossil state, has been found alive in the British seas at Zet-
land, in Belfast Bay, and at Exmouth, on the coasts of Guernsey
and Normandy, and lastly in the Mediterranean, which is the
specific home of the group.

Subgenus 12. Thecidea, Defrance.
Apophysis callously affixed to the bed of the valve.

48. Terebraiula ( Thecidea) Mediterranea, Risso^ Eur. M€rid. pi. 4.
f. 183.

Thecidea tesiudinaria, Michelotti.
• spondylea, Scacchi.

Hab. Mediterranean (attached to corals).

Thecidea is rather a difficult subject to observe, by reason of
its habits. It bears much the same relation to the rest of the
Terebratula that Hinniies bears to Pecien. The pedicle, like the
byssus in that genus, loses its function and is dispensed with,
and the animal affixes itself by the shell. The shell, as in most
such instances, is of very callous and irregular growth, and it is
only by the casual development of its structural details in a
numerous series of specimens that its characters can be ascer-
tained. In some fossil forms of Thecidea a minute terminal fora-



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Geographical Distribution of the Terebratube. 187

men has been shown to exists but I find no trace of one in the
recent species. The umbo of the ventral valve is largely pro-
duced into a thickened spondyloid beak ; and in its front area a
large triangular rudimentary deltidium is soldered* The dorsal
yalve^ ruddy indented and flattened, is of a horse-shoe shape;
and the ventral valve, densely convex, is rayed outwardly with
close-set grooves, which produce serrations on the inner margin.
The apophysial system is modified into a fixed ridge in the
bed of the valve, accompanied by a profusion of little indenta-
tions. When describing Theddea twenty years ago (Conch.
Syst, i. p. 184), I remarked that " the upper valve is flat ^d
curiously indented, as if to fit certain corresponding parts in the
body of the animal. These indentations, which spread round in
a semicircular direction from the hiuge, look exactly as if they
were picked out in wax ; and in a specimen which I have ex-
amined with considerable minuteness, they were filled with the
dried remains of numerous fine ciha/^ No sort of loop had
been observed in Theddea, and it is now obvious that this in-
dented bed of the ciliary arms is a modification of it.

Geographical Distribution.

It is difficult to generalize on the geographical distribution of
the TerebratuUe, with the hope of arriving at many conclusions
of interest, wi£hout embracing the fossil species. As might be
expected in the case of a tribe of animals which existed so much
more abundantly in the Silurian seas, and are perhaps destined
at no very remote period to disappear altogether, they are much
scattered, and are not abundant in individuals. Nevertheless
there are few genera of mollusks of which the habitats and specific
nature are now so well known. Of the 48 recorded species of
Terebratula (cited rather at random by authors at from 60 to 70 in
number), 4 are based upon siugle specimens of somewhat doubt-
ful specific value, without any information as to their habitats—*
cancellata, Bouchardii, transversa, suffusa; but their relationship



Online LibraryMassachusetts. Board of Harbor CommissionersThe Annals and magazine of natural history; zoology, botany, and geology → online text (page 21 of 56)