MISCELLANEOUS NOTES. 643 



A few eggs, similar to those above described, were subsequently found on 

 cabbage leaves on the College Farm ; but these were not reared success- 

 fully. 



It is not unlikely that the gaps in the life-history will be worked out 

 soon, now that something has been known of the nature of the important 

 ■stages — egg, nymph and adult. 



T. V. RAMAKRISHNA AIYER, 



First Asstt. to the Govt. Entomologist. 



aokicultural college axd research 

 Institute, Coimbatore. 

 February 1913. 



No. XL.— LIFE-HISTORY OF HELICOMITUS DICAX, Walk. 



(With a Plate.) 



The complete life cycle of Helicomitus dicax ordinarily occupies a year, 

 it may however, extend to more than one year and probably even two 

 years. The imago emerges at any time during the hot weather. Eggs 

 have been collected in May, July, August, October and November and 

 they were not in a state of hibernation or eestivation. The egg, pvipa and 

 imago stages are short, lasting for several days, while practically the whole 

 of the long period of the life cycle is passed in the active larval state, the 

 larvee being active even in winter. The period occupied by the complete 

 metamorphosis was in one case as follows : — 



One egg-cluster was collected on the 12th August 1911. 

 The eggs hatched on the 16th August 1911. 



Pupation took place (except of one) from 16th to 30th July 1912. 

 Imagos emerged from 3rd to 17th August 1912. 

 One larva did not pupate. It was apparently full-grown, but it did not 

 form any cocoon and continued to feed. It was fed and was actually 

 observed to feed continuously until the 25th February 1913, when it died, 

 probably from starvation as food was supplied to it sparingly. It was 

 discovered dead on 23rd March 1913, death not being suspected till this date. 



The egg. — Each egg is cylindrical, measuring about 1'5 m.m. in length 

 and about 1 m.m. in breadth, with the ends slightly convex or flattened. 

 The surface is smooth and around one end, which may be called the 

 anterior end, there is a marking or suture. When the egg hatches, the 

 shell splits along this suture, so that the end forms a lid-like structure, 

 which however does not fall ofi", but sticks to the shell at one place in a 

 somewhat curled-up condition. The colour is dull dirty-brown and hardly 

 undergoes any change. At the centre of each end, there is a dark coloured 

 or black spot. 



The eggs are deposited in clusters (see plate, fig. 1) neatly arranged in 

 isolated straight rows, their long axis being at right angles to the length 

 of the row. They are gummed to the surface of the substratum and 

 placed side by side touching one another. The anterior ends of the 

 majority of the eggs in the same cluster are turned in the same direction, 

 and it is curious to notice how only a few may be turned in the opposite 

 direction there being no irregularity or a symmetry in the arrangement of 

 the eggs. Thus out of 43 eggs on a leaf of Polyalthia longifolia, 39 were in 

 a row on the upper surface near the margin in the apical half and four in a 

 row near the apex on the lower surface. Out of the 39, the anterior ends 

 of 37 were turned in the same direction towards the margin of the leaf, 

 while those of the remaining two were turned in the opposite direction. 

 28 



