4y6Bif h tSgx.] THE TROPieiM, AQUIOULTURlSvT*' 
up 
No. 
X 
2 
3 
Lftrvee. 
20 
63 
191 
Pupje. 
3 
7 
12 
The average per tree is 
No. 1 
5-76 
Beetles. 
1 
3 
2 
17-75 
Totala. 
23 
71 
206 
3 
51-60 
Thia ahows that a tree left iyiog ou the ground 
daring the monsoon, when it is kept constantly 
damp, does not develop many beetles, but suoh a 
tree if left out during the dry weather will develop 
almost all the eggs deposited On it. This points (o 
the urgent neoessKy of burning the trees as aoou as 
pulled out. 
The greatest number of borers I found in one tree 
was as follows :— 
Tree taken out July 8th, 1887, out up September 8th. 
60 Borer Grubs, or Larvse 
23 Pupee 
1 Fly, Beetle or Imago 
93 totki iQ ihe tree in yanowt {pbaf)f 9 
Broadly speaking the temperature represents the aver- 
ages of the maximum and minimum observations, 
and they do not as a rule vary in South Coorg more 
than live or ten degrees from those given. 
A oonsideratiou of the foregoing explains why 
'shade," reoommended by Dr. Bidie, who saw 
its good effects on the PoUi Bettas where it 
had been planted by Mr. Mincbin, who I am informeu 
saw its good effect in Munzerabad, is eo useful in 
retarding borer development. 
The mean minimum temperature must not lall below 
65 deg. F. orthe development of the beetle is retarded, 
and Bbade by shuttiug out the sun's rays lowers 
the temperature. 
The egga if kept at a temperature uf 36 deg. for 
24 bours are all killed, few resist a temperature of 
40 degi ; but if tbe temperature is mamiained at 
from 80 deg. to 90 deg. almost all the eggs will give 
forth larvsB in about 10 days. Hence wnen a very 
dry season with hot east wind occurs " borer " 
faiiorea are more numerous. It is also the reason 
why borer has been so much worte in the 'i Bamboo" 
districts than in tbe forest and ghauts, and is the 
chief reason for shadti becoming necessary in the 
hot eastern districts. 
The beetle when depositing its eggs selects a crack 
or crevice ou the eunny side of the tree, and 
avoids the side upon which the mouaoon rain 
beats. Every shower of rain destroys the egge 
Which have not been so placed that they are kept 
dry. Shade does great good by retar'ling the deve- 
lopment of the eggs, so giving the trees a greater 
chance uf being freed by the rain from them. 
To satisfy myself as regards the influence of moisture 
I conducted a serids ot experimenis on the .deve- 
lopment of tbe eggs, wbioh I will briefly describe. 
Twelve " borer " trees tufcen out in May were 
chosen tor the experiment : they were as equal as 
possible in size ; tbe primaries were out oft. 
No. 1. Four of the stems were placed standing 
in a disb, with soil up to tbe old ground level, on 
the top of eacn was placed a pad of wool. The 
whole was enclosed in a muslin cage which was kept 
about one foot clear of the trees. Ko. 2 was the 
same as Nov 1, only the pad uf wool was omitted. 
No. 3 was tbe same as No. 2. In Nos, 1 and 2 the 
soil was kept constantly damp, and in No. 1 the 
pad of wool also ; No. 3 was quite dry. Previous ex- 
periments had Bbown that a temperature of 80° to 
90" was most favourable to the development of the 
eggs, and I maintained that temperature as uearly 
as poasible. 
No. 1 was damp all over 
No. 2 „ „ at the root 
No. 3 „ „ dry 
A beetle escaped from one of the trees in No. S 
in August, and in September I out up the trees with 
tbe following resulis: — 
Trees brought in May 13th, 1888. Trees out 
Sep. 9tb, 1888. 
of development, One beetle escaped before I cut up 
the tree, so that there were altogether 84 "borers" 
in that one tree. 
This tree was kep. carefully dry, and at au equable 
temperature varying from about 65° to 80°. 
Under favorable circumstances the life hiatjiy as 
follows: — 
The beetle deposits the eggs in a crevice ot the 
bark on the sunny side of the tree ; in about ten days 
tbe larva hatch out, but it may require 15 tu 'M. 
The larva works on its side and cannut advance 
unless there is a resistance behind : this tbe newly 
hatched insect obtains from a projection or corrugation 
of the bark ; in 24 houra or less the creature is buried 
under the bark. Once in the tree it advances, com- 
pacting the sawdust-like matter it exoretos by ad- 
mixture with a gummy substance which aided uy luo 
pressure of the insect lorcing itself up against lue woud 
It is devouring becomes almost as hard as the surtouua- 
ing wood, and fills the tunnel behind the auvancing 
larva. Tbis work goes on for from three to flvd moncbs, 
when having reached its full deveiopmenii iba latva' 
having advanced to within about i inch of tue barn 
undergoes tranaformation entering the pupa atnte. 
In this state it is covered by a thin transparent en- 
velope, and lies with its head towards the oark and 
the tail towards the centre | it remaina lu this state 
till the tempratase is suitable, probably about three 
weeks or a month, when it undergoes itd final change to 
the beetle which eats its way out. If the larva uao not 
worked near enough to the bark before changing, the 
beetle may fail to escape, there being more vVooU than 
it can consume. 
From egg to beetle the average duration of the in- 
dividual lite ia about six montbs, the majurny uf tbe 
race developing in May and October, 
As 1 have already exceeded my limit 1 must conclude, 
thougfi 1 bave omitted a description of the Beetle ana 
Borer Grub, and merely given an outline ot liie most 
important facta. 
WILLIAM PKINGLE, m.s.c.i., Agricultural Uhemist. 
Bangalore, 3rd July i8i)l. 
PART IL 
This paper gives a description of the Hulometa- 
bolio insect, tbe habits ot wbioh were describou lu my 
last article. 
The beetle is classed with the great natural divi- 
Bion of insects the MandibtUata. It belongs tu tne 
order Coleoptera, suborder Arambyoida {Lonyicoma 
Latreille) ot which there are acooramg tu i'^cKura 
about 4,UU0 named species, all more or l^ss ae- 
atructive wood borers. Of these the genua Vlytus 
to which the coffee borer belongs ia well kuuwn in 
England from its representative the Wa^p Boetie 
{filytm arietis), the larvss of which do noi However 
cause muob loss, ohietly confining themselves to old 
posts and dead timber. In America there are several 
species which do great damage: of these C. inctue 
the hickory tree borer and 0. robinias the loousi iree 
borer resemble in shape and size most cloooiy ino 
(Jlytns coffeophagus, tbe Ooffoe Borer. But mere are 
several important diflerences between them uoi only 
in the marking of the elytra, but in ineir sbape 
aleo. They do not quite cover the body wliicn ex- 
tenda about one-twentieth (,-050) ot an men oeyoud 
them. When olosed,over the wings thep^sicrior ex- 
tremity is almoet square across, on tbe outaiuo oi u 
a small apike projects. 
Further diherences between the Coffee Borer and 
other known species of olytus will be discuvereu oy 
carefully reading the following description ol tuo lu- 
aeot, and comparing it with tbe description of named 
apecies. 
The ova (egg) is cream-colored, and is just largo 
enough to be visible to the naked eye. 
The latvce are when full grown about one to one and 
a quarter inches long, about two-tenths ( luu; m 
diameter at the anterior extremity ot ino Duuy 
tapering gently down to fifteen one-hunuredtos 
(•150> at the poaterior. Ihe body is uiviued 
