10 LIFE-HISTORIES OF PTEROPHORIDA 
Infe-history. The egg is oval, cylindrical in section, and measures about 
0'5 mm. in length. It appears smooth, though the outer surface is actually 
reticulate ; the colour is an indefinite bluish-green, becoming yellow before 
hatching. Eggs are laid in spots determined by the ability of the moth to 
assume a position of rest ; they never rest on the upper surface of a horizontal 
leaf but can rest on the lower surface of a leaf or place at any angle from the 
perpendicular to the horizontal ; they appear always to hang from an object 
rather than rest on it ; on the broad leaves of cucurbitaceous plants, eggs are 
laid on the lower surface ; on the alternative foodplant, pigeon-pea, they are 
laid on the flower-buds and young pods. Eggs are usually laid singly, often 
only one on a pod or flower-bud, several on a young leaf. In the Insectary, 
193 eggs were laid by two moths, all being laid at night. The eges hatch in 
two days in warm weather up to six days in the colder weather of the North 
Indian winter :— 


Eggs laid Eggs hatched Duration 
7th September 9th September 2 days. 
8th aS 11th | As BY ap 
9th “0 12th oe 3 Se 
16th ¥ 19th + Be oar 
9th February 15th February Cars; 


t 
The larva emerges from the egg by biting away a small portion and then 
pushing through. The empty egg-shell is not eaten. On hatching the larva 
is about a millimetre long ; the head is dark brown and shiny ; thereis a distinct 
prothoracic shield; the segments are well marked and on each segment 
there are five tubercles bearing from one to three hairs each ; these tubercles 
are regularly arranged and form rows along the body; the round spiracle 
lies between the second and third tubercles. There are three pairs of thoracic 
legs and five pairs of prolegs. | 
The larva is of a yellowish-green colour on hatching, becoming green as it 
grows older and remaining of that colour ; on the pods of pigeon-pea, which are 
coloured usually in green with brown stripes, the larva also has a lateral brown 
stripe and assimilates very closely to the colour of the pod ; on green leaves 
of pumpkin, etc., it is green and this assimilates it to the pure green of the leaf. 
The larva alters little in appearance, during the various instars ; in the last 
instar the dorsal three black tubercles are developed into more prominent 
protuberances ; the first and third are yellow, the second black, each with 
