r>?s2 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XX. 



and occasionally with bed bugs. They preyed on each other, when no food 

 was available. They used to sit with the body hidden under dust or 

 rubbish and lie in wait with open jaws for any passing silver-fish. They 

 were not infrequently dragged to some distance by the prey, but hardly 

 ever let go the hold. The silver-fish was often made motionless by pricking 

 before being supplied and the larvse woidd come and suck it. The winter 

 was passed in a more or less resting but not a perfectly dormant condition. 

 The larvte stirred out if touched. They wanted no food at the time. 



The larval stage lasts about a year. Some hatched on the 12th April 

 and formed cocoons the next year between the 20th and 30th March. 



Pupa. — The larva pupates in a round cocoon formed by binding particles 

 of sand with a very thin white silk exuded from the hind end. A retrac- 

 tile straight yellow needle-like process is thrown out and taken in alternate- 

 ly, which applies the silk to the particles of sand by touching them with its 

 tip from which the silk appears. All this time the larva either contracts 

 or expands the body and keeps on turning round and round slowly. The 

 finished cocoon measures about 4 m.m. in diameter and looks like a small ball 

 of particles of sand cemented together loosely. Before turning into the pupa 

 the larva rests for some time inside the cocoon with the head doubled on 

 the ventrum. Such a resting larva is pictured in fig. 3. The pupa also 

 remains ventrally curved inside the cocoon. Before emergence of the 

 imago, it begins to straighten the body alternately. Thus the head strikes 

 against the wall of the cocoon. In this way a hole is burst open in the 

 wall of the cocoon through which the head with a portion of the thorax is 

 pushed out. Then the skin bursts along the middle of the thorax and head 

 and liberates the imago. Fig. 4 pictures an empty cocoon with the pupal 

 skin protruding out of it. The period of the pupal stage is about three 

 weeks. One formed cocoon on 20th March and emerged as the winged 

 insect on 12th April. 



C. C. GHOSH, 

 Assistant to Imperial Entomologist. 



Pusa, Bengal, June 1910. 



EXPLANATION OF PLATE. 



Crocejilipennis, Westw. 



1. Young larva, 20 days old, 1st stage, X 25. 



2. Larva, 7-J months old, x 18. 



3. Larva resting inside cocoon before pupating, x 18. 



4. Cocoon with the pupal skin protruding out, showing how the imago 



emerges, x 16. 



5. The adult insect, x 6. 



6. A single egg, x 18. 



