January 2, 1888.] THE TROPICAL AGRICULTURIST, 
445 
and strong like new gutta. Other samples, kept un- 
der similar conditions, foil into dust as so m as they 
were touched ; and Mr. Hancock tells me that ho 
cannot account for the difference between them. 
It may be mentioned as probable that the rapid 
decay of thin-sheet gutta it* often duo to the action 
of ozone, as (his reagent attacks gutta (and rubber, 
too, for the matter of that) with intense energy ; a 
thin leaf of gutta falling to dust almost immedi- 
ately in strongly ozonised oxygen. 
Coming on the market as a material essentially 
differing from ordinary gutta, and under another 
name, the product of the bullet-tree is considerably 
handicapped in tin- market; and this more especially 
as the supplies have arrived at irregular intervals. 
The speculating corumercialist has frequently availed 
himself of these circumstances to purchase bullet- 
tree gutta at a simply nominal price— sometimes 
only (i cents a pound — but the manufacturer seldom 
gets hold of it under the matket price for best 
gutta. 
The capabilities of supply in British Guiana seems 
to be enormous, and if the misleading term Batata 
were dropped, and relations opened directly with 
manufacturers, an enormous trade could probably be 
done in this article. 
Even though more carefully collected and less adulter- 
ated than othi r guttas, there is still room for improve- 
ment as regards the collection, and if some system 
of coagulation could be systematically employed, the 
quality of the product would bo enormously advanced, 
or rather, one should say, the deterioration of the 
hydrocarbon by oxidation would be minimised. The 
difficulty is to fiud a coagulating material which shall 
be sufficiently cheap, and which, if some O'f it remains 
in the product, shall not work mischief. 
I may point out that it is desirable to mould the 
gutta-percha rather in compact masses than thin sheets, 
as other things being t>qual, the oxidation is directly 
Droportiouate t« the surface exposed to the air and 
light* 
Very much more might be said as to the condition 
and possibilities of tho gutta-percha industry in 
British Guiana ; but spaos does not admit of it. 
India-rubber was shown in the British Guiana 
department, and it appears in irregular balls of from 
2 to 1 inches in diameter. This rubber appeared (with 
the exception of a few balls which seemed to have 
been damaged by contact with grease) to be sound 
and of good quality, although not very clean. There 
seems to be no certain information as to the origin 
of this rubber; but there is but little doubt that 
a good deal of it is obtained from the touckpong-tree 
already alluded to in a foot-note. Tho tuckpong grows 
very rapidly, is abundant ou the Oanje, and a variety 
growing neir tho coast has been identified by Professor 
Oliver, of Ivew, as one of the seventeen varieties of 
the Uapium biglandulosum (Arg). The touckpong is 
said to be oue of the KuphorbUceous order, and the 
Pomeroou variety appears to be regarded by Oliver 
as one not hitherto recognised. 
The partly-dried juice is boilo I in water and made 
into balls ; in formor times it has been too much the 
custom to mix the milk of the touckpong with that 
of the bullet-tree; but one cannot too strongly insist 
on the necessity of keeping the two products separate. 
A tree called liarta-balli yields a very inferior rubber, 
and from what I can gather, the only thing to bo 
observed with regard to this troo is to suggest to 
tho authorities to keep its product sepatate from that 
of the touckpong, if, iudeod, it is considered worth 
umbering. The admixture of batta-balli milk with 
tho gutta-percha milk is likely to be very injurious. 
•Jenman, in tho report quoted, refers to the Imlata 
milk — for which the collectors receive so much per 
gallon— having occasionally been mixed with the mi l; 
of the treo called by the people touckpong. Now the 
tonokpong yields a true rubber; and it may be that 
forue of tho samples of Imlain which werr pronounced 
to bo intermediate in properties between gutta and 
rubber wero prepared from the mixed milks. Tho 
collectors should bo instructed to carefully avoid any 
•dmixiuro of tbit kiud. 
It seems probable that the touckpong is the tree 
generally known as the Hrvea Giianensis ; but as 
regards this mat'er there seems to le no very certain 
information at present. — Indiarubber and Guttapercha 
Journal. 
INSECTS INJUEIOUS TO FRUIT CROPS. 
The report on insects injurious to fruit crops prepared 
for the Agricultural Department by Mr. C. Whitehead, 
F.L.S., F.G.S., was issued on Tuesday. The introduc- 
tion states that the report relates entirely to insects 
injurious to fruit crops, and to those among them which 
cause the most serious losses to fruit cultivators. There 
are others whose injurious effects are comparatively in- 
considerable, so that it has not been deemed necessary 
to describe them here. For the most part the insects 
which have been described are formidable enemi-s, 
and in many cases more formidable because their 
work of mischief either is attributed to other cause, 
or is not discovered until it is too late to adopt 
means of prevention, or to apply remedies. Some 
of these insects cause the failure of an entire crop, 
as, for example, the Ilyponomeuta pudella, or ermine 
moth, by whoso action the apple crop has in some 
seasons been destroyed throughout large areas of 
orchard land ; while others, like the Carpocapsa pomon- 
etla, or codlin moth, materially damage the appear- 
ance and quality of the fruits. Fruit growing is a 
most important branch of agricultural industry, and, 
taking the average of seasons and of the various fruit- 
producing districts, has proved profitable when other 
crops hive not auswered. Tho acreage of fruit land 
in England, according to the statistics given in the 
" Agricultural Returns," was 197,539 acres in 1885, 
and probably at this present time amounts to over 
200,000 acres, as there has been a gradual increase in 
the acreage during the last ten years at the rate of 
about 3,500 acres per annum. Besides this acreage, 
properly termed "arable or grass lauds used for fruit 
trees of any kind" in the "Agricultural Returns,'' 
which bond fide farm fruit land, there is a large aggre- 
gate acreage of gardeu grouud appertaining to all 
houses in the country from tho nobleman's mansion 
to the labourer's cottage, upon which much fruit is 
produced, and whose full yield is most important to 
the owners and to the consumers of fruit, which in its 
natural state, or preserved, forms an important aud 
most wholesome part of the diet of the people. Inform- 
ation as to the history aud habits of the chief insect 
spoilers of the fruit crop may, it is hoped, tend to 
their discomfiture, and to the larger production of the 
fruit lands of this country. 
The following insects are mentioned in the report: — 
The raspberry beetle (Byturus tomentosus), the green 
chafer (Cetonia aurata), the strawberry weevil (Otioiyn- 
chus sulcatus), the red-legged garden weevil (Otiorynchus 
tenebricosus,) the raspberry weevil (Otiorynchus picipesj, 
the apple bhxsom weevil (Anthonomus pomorum), the 
nut weevil (Balaninus nucum), the pear saw-fly (Selati- 
dritt ctrasi), the gooseberry and currant saw-fly (jVtma- 
tus grossularia), the currant clcarwing (.TZyeria tipuli~ 
formis), the goat moth (Cossus liyniperda), the wood 
leopard moth (Zeveera oiculi), the l.ickey moth (Cli- 
siocampa Xeustria), the common vapourer moth (Oryyia 
antiipta), the magpie moth (Abraxas grossidariata), 
the winter moth (Chcimatobia brumata), the co.i iu 
moth (Carpocapsa pomonctla), the small ermine moth 
(Ilyponomeuta padjta), the sirawbe'ry moth (Peronca 
comariana), tho currant borer (Lunpronia capitttia), 
tho raspberry shoot borer (Lampronin rubietla), the 
cherry aphis (.Wyzus ccrasi), tho apple aphis (Aphis 
mali), tho plum aphis (Aphis pruni,) the cur ant aphis 
(Rhopalosiphum ribis), the woolly aphis [SchitOKtura 
laitiyera), the mussel scale (ilytilaspis pomi.ru in , tho 
red spider (Tetranychut teiarius), the I'lack currant 
mite (Phytoptus nbu), aud tho natural cut linos of 
injurious insects. 
Two reports by Mr. O. Whitehead, ■ l.s , v o 
were issued on Wednesday by the Agricultural 1> - 
partmcut. Tho first of these treats ol " lowr* In- 
jurious to Hop Plants." ou which subject Mr. White- 
head writes — Thero is au increased aud increasing 
