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surface. This would be in the present case even more striking if
the enumeration were more complete than it can pretend to be.
Some groups have not been worked at all ; this is the case with
the Diptera^ and of the Hemiptera only the Coccid<e have been
catalogued. Others, it is obvious, have been only touched super-
ficially. 'The publication of what has been done may encourage
working naturalists to correct errors and to accomplish, as perhaps
has never been done yet, a complete census of every form of life
occurring spontaneously in a small but well defined area.

** I am glad to take the opportunity of acknowledging gratefully
the assistance which has been given to those who have suc-
cessively had a hand in the work by a very large number of
individual workers in various branches of zoology and botany.
Some of the most important are enumerated in the following
•Table of Contents.' I see from the mass of correspondence
which has accumulated that there are a host of others, many
personally unknown to me, who have cheerfully rendered the
assistance which has been demanded of them on special points.
I find it impracticable to specify them all individually, and can
only beg them collectively to accept my appreciation of their aid.

" W. T. Thisblton-Dybr.
" Kew, February, 1906."



•• The abbreviations used are as follows :

" A. Arboretum. This includes the whole of what was formerly
termed * pleasure grounds.'

^^ B. Botanic garden. This division was formerly separated from
the arboretum by a wire fence, which ran near Unicom
Gate, by north end of Pagoda vista, along eastern side of ash
collection to Palace lawn.

" P. Palace and herbarium grounds.

*^ Q. Queen's Cottage grounds.

"R. Rock-garden.

" Strip. This is the piece of ground between the wall and the
Thames, extending from end of herbarium grounds to the
end of Queen's Cottage grounds."



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45
CONTENTS.



I.-FAUNA.

Mammalia. By a. H. Ponnett, M JL (6^ o^ p. 821)

AVM. By W. H. Hudson

Beptilia. By A. a«nther, Fh.D., F JLS

Amphibia. By A. aftnther, Ph.D., F.B.8

Pi8C66. By A. Oftniher, Ph^D^ F.B.S

Mollusoa. By H. H. Brindley

Bntomostraoa. By D. J. Sooorfield, f.b jls.

Myriapoda. By B. i. Pooook, F.Z.S

Orthoptera. By W. J. Luoaa, f.l.s

Neoroptera. By W. J. Luoaa, F.L.S

Coleoptera. By H. H. W. Pewrson, F.Lil

And D. Sharp, M.B^ FJLS

Formieids. By Lt-Col. C. T. Bingham

Oooeito. By B. Newstoad, A.L.8

Lepidoptera. By B. Soath, f.b^

OallB. By Prof. J. W. H. Trail, F.R.8

Oak-Oallfl. By B. A. Bolfe, AJi-S

Araneidea. By Ber. O. Piokard-Oambndge, F.R.S.

Aearina. By A. D. Michael, F.L.S

Hydrachnids. By Chas. D, Soar, F.B.M.S

8eorpionid». By B. i. Pooock, F.L.S

Annelida. By F. £. Boddard, F.B.S

Hirndinea. By Prof , Lankester, F Jt.6

Botifera. By Chas. F. Boueselet, F JLM^S

Porifera. By B. T. Glhither, FX.S

ProtOIOa. By F. B. Fritioh, D.8c., F.L.8

IL-FIiORA.

PhaneroganuD. By a. Niohoison, F.L.a

niioea. By O. NidholMm, F.LJ3

MnseineA. By B. a Salmon, F.I1.S

HepatioS, By Chas. H. Wright, A.L^

Lielionea. By 0. v. Darbidiire, M.A.

FnngL By a. Maasee, F.L.S. (^a^p.223) ...

HyxogtfUtres. By G. Mmwee, FJ1.8

Alg». By F. B. FritBoh, D.S0., F.L.S

Appbkdix.
Additional Coleoptera. By d. Sharp, M.B., f.b.s.



1

2

10

10

11

19
14
91
2S

26
25
221
2T
29
84
41
46
58
64
64
66
66
68
68
78
78



78
91
91
101
102
103
184
187



221



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VI.-NBW AND ADDITIONAL SPECIES OP PUNM
OCCXTSBINa IN THE BOTAL BOTANIC GARDENS,
KEW.

{With Plate.)

Ab might have been expected the entmieration of the Fungi
detected in the Royal Botanic Gardens, Kew, given by Mr. George
Massee, F.L.S., in the Wild Fauna and Flora (pp. 103-184),
although very extensive, has not by any means proved exhaustive.
The following are undescribed and additional species which have
been observed since the enumeration was in type : —

Dasysoypha absoondita, Masses (sp. nov.). (Figs. 1-6).

Ascomata 1*5-2 mm. alta, 1 mm. lata, gregaria, prime globosa
dein cupulata, stipitata, extus margineque pilosa, albida ; pilis
hyalinis, septatis, clavatis, 60-80 x 7-10 fi- Ascl cylindracei,



In the Fern house, on wood received from Jamaica.

Pileus 3-4 cm. broad ; stem 6-8 cm. long. Very remarkable
on account of the opalescent or iridescent tints of the thin,
white gills.

Bolbitius ombonatus, Massee (sp. nov,). (Figs. 12-13).

Pilefits tenuiter carnoso-membranaceus, subpellucidus, e conico
campanulatus dein explanatus, umbonatus, profunde sulcatus
glaberrimus, laete flavo-brunneus pallescens. Lamellae adnexae,
latae, subdistantes, acie integrae, f errugineo-flavae. Stipes sursum
attenuatuB, albus, basi marginato-bulbosus. Spcrrae ellipspideae,
ochraceae, 10 x 5-6 /i ; basidia spathulata, 23-25 x 10-12 p.

Gregarious on tan in the propagating pits.

This fine species approaches B. hulhillosxiSy Fr., in the distinctly
marginate bulb, differing however in its larger size, coarsely
sulcate pileus, and white stem. Probably an introduced species.



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Trioholoms saevum, Oillet. (Figs. 14-16).

A species that has in all probability been passed over as a form
of T. personatumy Fr., from which it differs in the fleshy pileus
becoming plane, incnrved margin glabrous from the first, absence
of violet colour in the gills, and very short, stout, violet,
squamulose stem.

Previously recorded from Sweden and France.

Among grass, Herbarium grounds.

Humaria pinetorom, Fckl. (Figs. 17-19).

This interesting fungus has been collected on fallen pine leaves
in the Arboretum. 6. Nicholson. Hitherto only recorded from
(Germany.



Description of the Figubbs.



BENTHAM TRUSTEES.






15. Section of pileus ; nat. size.

16. Basidia and spores ; x 400.

17. R^jtmaria ^netorum^ Fckl. ; nat. size.

18. Single plant ; x 8.

19. Free spores of same ; x 400.



S4186

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VII -MISCELLANEOUS NOTES,

Visitors during 1906.— The number of persons who visiM the
Royal Botanic Gardens during the year 1905 was 1,824,319. That
for 1904 was 1,579,666. The average for 1895-1904 was 1,334,549.
TTie total number on Sundays was 853,631, and on week-days
970,688. The maximum number on any one day was 61,183 on
August 7, and the smallest 70 on December 11.

The detailed monthly returns are given below : —



February


34,310


March


64,825


April


... 166,910


May


245,714


June


... 302,427


July


... 345,996


August


... 286,542


September


... 234,183


October


65,347


Norember


25,253


December


22,936



Mr. Kenneth Georqe Bubbridge, a member of the gardening
staff of the Royal Botanic Oardens, has been appoint^ by the
Secretary of State for the Colonies, on the recommendation of
Kew, Curator of the Botanic Station at Kumasi, Ashanti, a branch
station recently established in connection with the Botanical and
Agricultural Department of the Gold Coast



Mr. Edgar W. Foster, formerly a member of the gardening
staff of the Royal Botanic Gardens, and late Curator of the Botanic
Station, Lagos, has been appointed by tiie Secretary of State for
the Colonies, Assistant Conservator of Forests in the Colony,



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ROYAL BOTANIC GARDENS, SEW.



BULLETIN

OP

MISCELLANEOUS INFOEIATION.



No. 8.] [1906.



Vm-PLANT DISEASES.-IV. DISEASES OP BEET
AND MANaOLD.

It is a common saying among horticulturists and others that
long-continued cultivation of a particular species of plant makes
it more susceptible to disease than is the case with the same kind
of plant growing in a wild state. As a rule there is no real
evidence in support of such an opinion.

Exhaustion of the soil is a favourite explanation of **beet-
sickness,*' '* clover-sickness/' &c.^ but numerous exhaustive
analyses of the soil have clearly demonstrated that the essential
constituents of the soil have not been lacking ; and, furthermore,
the addition of fertilizers has not reduced the diseases alluded to.
On the other hand, these diseases have been clearly traced to the
direct action of animal or fungus parasites, and when these were
removed the disease disappeared.

The following is an attempt to deal in an intelligible manner
with some of tiie most destructive parasites attacking beet and
mangold, accompanied by a description of the methods that
experience has proved to be most effectual in checking the
same.

Beet Canker.

{Pionnotes betacy Sacc.)

This fungus sometimes destroys stored beet and mangold,
especially if sweating has occurred. Small scattered glairy, dingy
yellow spots first appear on the surface of the root ; these soon
spread and run into each other, forming irregularly shaped,
nodulose, subgelatinous crusts up to one and a half inches across,
varying in colour from ochraceous to orange.

Owing to the cells of the beet being disorganised and used up
by the mycelium of the fungus large cavities are formed, and,
aided by myriads of bacteria, the root soon becomes watery and
rotten, at the same time exhaling a very unpleasant odour.
Adjoining roots are quickly attacked, and if the disease appears
soon after the beet are stored a large percentage is pf ten logt,

1375 W( 4/06 Da^S 29 249Q9



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/



Fio. 1. — ^Beet canker. 1, appearance of a diseased beet ;' 2, section
through a diseased wart ; 3, fruit of the f ongrus ; 2 and 3 highly
magnified.

In some few instances I have detected this f angas on beet that
have not yet been lifted.

The substance of the fungus consists of a dense mass of slender
threads or hyphse imbedded in a glairy substance, the whole
forming a subgelatinous crust two to three lines thick. When
mature the entire sur&ce of this crust is covered with a dense
mass of colourless, narrowly spindle-shaped, slightly curved
three-septate conidia. These conidia germinate quickly on a moist
surface when mature ; a small number on the point of a lancet
inserted into the flesh of a perfectly healthy beet formed a disease-
patch one inch across in 11 days.

This fungus also attacks potatoes, as I have proved by repeated
inoculation experiments, and it is probable that the frequent cases
of rotten stored potatoes is caused by the parasite under con-
sideration, which, judging from the description given, appears to
be identical with the fungus called Pionnotes rhizophilay Sacc,
said to attack potatoes and dahlias.

Preventive measures, — Qreat care should be taken not to include
roots showing symptoms of the disease when storing ; further-
more, the roots should be thoroughly dry, so as to avoid any
possibility of sweating in the pit. From personal observation,
also from information, I find it appears to be a common practice
when removing stored roots to either le^ve diseased specimens oa



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the ground to rot and disappear, to take them to the piggery, or to
throw them on to the manure heap. All methods are equally
unsatisfactory, as the mycelium and conidia present continue to
grow, and being spread far and wide endanger future crops. The
only safe method of dealing with such diseased material is to
bury it without delay.

Bbbt Rust.

(JJromyces hetaey Ktihn.)

This fungus occurs on mangold and beet, also on wild beet
{Beta maritima\ and when present in quantity the crop is con-
Biderably reduced owing to the destruction of the leaves, whereby
the root is arrested in its growth, and the amount of sugar
considerably lessened.

The three stages in the life-cycle of the fungus are all produced
on the same plant The aecidium or "cluster-cup" condition
appears in spring on the leaves and leaf -stalks under the form of
minute cavities or cups with white torn margins, which are usually
arranged in groups on a pale spot. The cups when mature are
filled vrith yellow spores. Other minute bodies called spermo-
gonia, whose use is unknown, precede or accompany the
aecidia.

The aecidiospores, scattered by wind, rain, or the movements
of animals, are deposited on other leaves of the host, where they
germinate, enter the tissue, and in a short time give origin to
numerous minute warts that burst when mature, and liberate
little heaps of brown uredospores, which are often so abundant
as to give to the surface of the leaf the appearance of having been
sprinkled with snujff.

It is this uredospore stage that does the damage to the crop.
The uredospores are produced in immense numbers, and are
capable of germination at once, are dispersed wholesale, and infect
the crop with great rapidity when conditions are favourable, the
requirements being moisture on the surface of the leaves and
some means of spore dispersion.

Later in the season the teleutospores, representing the third
form of spore produced by the fungus, are formed in small
clusters on the leaf-stalks, or sometimes along with the uredo-
spores. The teleutospores remain in an unchanged condition
until the following spring, when they germinate and infect the
leaves of young beet plants, giving origin to the aecidium stage of
the fungus.

Preventive measures. — Removing the leaves bearing aecidia or
^cluster-cups" is effective, as the aecidiospores give origin to the
uredo stage, which, as already stated, is the condition that does
the real damage to the crops. Where hand picking is out of the

nition, on account of the large quantity grown, spraying on the
appearance of the disease with dilute Bordeaux mixture or
with a solution of potassium sulphide will check the spread of
the disease.

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The disease is not present in the seed, although its early
appearance on seedlings has led some to sappose this to be the
case. The crop always commences perfectly free from disease,
and its appearance is due to the plants having been infected by
teleatospores formed daring the previous autnmn. Rotation of
crops does mnch towards guarding against the disease. If beet or
mangold be sown on ground that produced a diseased crop the
previous season infection is almost certain to result, since, however
much care may be exercised in removing all diseased leaves,
numerous teleutospores are certain to fall to the ground, where
they remain unchanged until the following crop is ready for
infection. It is therefore advisable not to grow the same crop for
two years in succession on the same ground.

Badly diseased beet-leaves are injurious to stock, and even if this
were not the case it is perfectly certain that when such leaves
are placed in the piggery, or given to cattle, myriads of teleuto-
spores in a condition for germination are placed on the land along
with the manure, and a diseased crop is the result. The safest,
and in the end the most economical method is to collect all diseased
" tops '* that are twisted ofE when the roots are lifted and bury
them ; the small amount of fodder or manure so sacrificed is cer-
tainly much less than the risk— almost a certainty — of having an
infected crop the following season.



Leap Spot.

{Gercospora heticola^ Sacc.)

Probably the most destructive leaf disease to which beet and
mangold are subject. The first external indication of the fungus
is the presence of numerous minute, roundish pale spots on the
leaves and leaf -stalks. These spots continue to increase in size
for some time, becoming irregular in shape, and often run into
each other, forming large irregular blotches which are pale at first,
and often bounded by a dark line ; eventually these blotches,
which show on both sides of the leaf, become darker in colour,
and the entire leaf becomes almost black, shrivels, and dies.

If a diseased spot is examined under a magnifying glass very
minute erect hair-like bodies are seen on the sui^ce, and under
the microscope these tufts are seen to consist of clusters of pale
brown fungus-threads or conidiophores, each bearing one or more
long, slender reproductive bodies or conidia. These conidia are
dispersed at maturity and infect neighbouring plants. It is stated
that those conidia that are carried to the ground by rain or on
fallen diseased leaves remain alive during the winter and infect
young beet plants the following season.

As a rule the plants are not killed outright by this disease, but
the growth of the root is checked, hence the total yield is reduced.
From the evidence afforded by analysis Professor Pammel, an
American vegetable pathologist, remarks as follows in regard to'
sugar beet : — " 1 think it is safe to say that the amount of sugar
in the beet itself is scarcely diminished. The loss comes n^inly
fron^ a smaller an^ount of the total product."



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Fia. 2.^Leaf spot 1, appearance of a diseased leaf ; 2, frait of
the f nng^os, highly magnified.

Preuentive measures. — Spraying with Bordeaux mixture checks
the disease if operations are commenced on the first appearance of
the fungus. The following results of this method are recorded in
the New Jersey Agric. Coll. Expt. Station Report, 1896 :— " The
foliage of the bordeauxed plots was not materially injured, and
when harvested showed an increase in weight over the average of
the two checks of 77*5 per cent. The root systems of the sprayed
plot showed a corresponding increase of 46*5 per cent."

Diseased leaves should not be allowed to decay on the ground,
otherwise the conidia present would be likely to inoculate a
succeeding crop.

Beet Mildew.

{Peronospora Schachtti, Fuckel.)

The young heart-leaves of beet and mangold are frequently
attacked by this fungus, which, when present in quantity, often
kills the plant when favoured in its development by damp



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54

weather. Its extension is checked by a spell of dry -weather but
even under those circumstances plants that have been attacked
contain but a small amount of sugar.

The fungus appears as a very delicate lilac-coloured mould,
which frequently covers the entire under surface of the leaf, and
in some instances appears also on the upper surface. Infected
leaves are readily recognised by being deformed and twisted, and
by the presence on their under surface of the mould, which con-
sists of a dense forest of slender threads emerging through the




Fio. 8. — Beet mildew. 1 , appearance of a diseased leaf ;
2 Bommer fruit of the fongtis; 3, resting spores of the
fongiiB ; 2 and 3 highly magnified.



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stomata, each thread being much branched at its tip, and each
branch bearing a minnte elliptical conidiam or reproductive body.
These conidia are carried by wind or washed by rain from one
leaf to another, where they germinate, and soon form a new
centre of disease, from which conidia are liberated in rapid
succession and in great numbers. In addition to the surface
mould other bodies called oospores are formed on the mycelium
of the fungus present in the tissues of the leaf. These bodies are
carried to the ground by the decaying leaves, where they remain
unchanged until the following season, when they germinate, and
if beet or mangold be present the plants are infected.

PreverUitje measures. — Avoid sowing beet or mangold on ground
that has produced a diseased crop of the same kind the previous
season ; in &tct it is not good policy under any conditions to
attempt two root crops on the same land in succession.

It has been suggested that when plants have been attacked by the
fungus and have afterwards recovered, the mycelium hybemates in
the neck of the rook, and appears the following season, producing
a crop of conidia ; it is therefore important not to plant roots for
the purpose of producing seed that were grown in an infected
area.

If the disease appears among young plants, spraying with dilute
Bordeaux mixture will arrest the spread of the fungus.



Violet Root Rot.
(Bhizoctonia violacea^ Tul.)

This very destructive disease is recognised by the presence of a
more or less dense violet or brownish-coloured mould on the
roots. The life history of this fungus has not been followed;
several species have been proposed ; but as suggested by Tulasne, a
French mycologist, probably all are forms of one species. When
young plants are attacked they usually die gradually, whereas
when the root is fleshy death is somewhat sudden ; large holes
are formed in the flesh, the surface being covered with the brown
mycelium of the fungus. Numerous small dark-coloured sclerotia
or compact masses of mycelium are also usually formed in the
decaying tissues of the host ; these are liberated in the soil, and
enable the fungus to continue its existence from year to year.

The disease occurs in patches in the field, which continue to
increase in size. A single beet is first attacked from which the
mycelium spreads in the soil, attacking in turn neighbouring
plants. Owing to the great number of different kinds of plants
on which the fungus can live, it is very difficult to eradicate
when it has once gained a foothold. Carrots, turnips, potatoes,
lucem and saffron are all attacked. It has been stated that saffron
and potatoes have been attacked after an interval of twenty years'
rest from such crops on land that had previously produced a
diseased crop. Spores or special reproductive bodies are unknoVn,
the fungus reproducing itself from year to year by means of its
mycelium and sclerotia. It is very probable that the fungus
derives food from various weeds as well as from cultivated plants.



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Preventive measurea. — Good cultivation, alternation of crops
and destruction of weeds afford the only means of successfully
combating the disease, which fortunately does not attack cereals.

Bbbtroot Tumour.

(JJrophylictis leproideSy P. Magn.)

This disease was first obseryed attacking beetroot growing in the
grounds of the School of Agriculture, Rouiba, near Algiers.

The disease is characterised by the presence of one or more
brain-like outgrowths or tumours, each attached by a narrow neck



FZO. 4.— Beetroot tumour. 1, appearance of a diseaaed
beet ; 3 spores of the fungus, highly magnified.



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to the upper part of the beetroot, and originating from rootlets or
leaves that are inoculated by the fungus, which in the first instance
enters an epidermal cell causing it to swell, and subsequently pro-
moting rapid division and multiplication of surrounding cells,
until eventually an irregularly formed mass of tissue results.
When fully developed these outgrowths attain a large size, and
when cut open present a cavrernous or spongy appearance inside,
the cavities being filled with masses of dark brown, thick-walled
resting-spores, resulting from the conjugation of male and female
cells, borne on distinct hyphae or strands of mycelium.

The mature resting-spores are large, with a smooth, thick, dark
brown wall, elliptical, and are produced at the tips of very slender
hyphsB which have a globose, colourless swelling just below the
insertion of the resting-spore.

Quite recently, the fungus under consideration, or one very
closely allied, has attacked potatoes in this country, causing coarse,
scabby outgrowths on the surface of the tubers.

Preventive measures. — Diseased plants should be removed and
burned the moment they are observed ; if allowed to remain and
rot on the ground, the liberated resting-spores would endanger
future crops.

White. Rust.
{Gystopus iliti, De Bary.)

This fungus has only hitherto been observed on sugar-beet in
one locality in the United States, but as allied species often prove
destructive to other plants, especially those belonging to the
CrucifersB, such as cabbage, radish, horse-radish, &c., it is possible
that the mangold and beet may also suffer when attacked under
conditions favourable for the rapid extension of the parasite.

The disease is indicated by the presence of pure white shining
slightly raised spots about one line across on both surfaces of the
living leaves. These patches constitute the conidial or summer
form of fruit, and are developed below the epidermis of the leaf,
which becomes ruptured when the spores are mature. The spores
germinate quickly when placed in water or on a damp suiface ;
hence those that are washed by rain or blown on to the surface of
a damp leaf soon give origin to a new rust pustule, which in turn
liberates spores.

Resting-spores or oospores are also formed on the mycelium of
the fungus present in the tissues of the leaf ; these remain in an
unchanged condition until the following spring, when they ger-



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