MISCELLANEOUS NOTES. 647 



young silverfish extricated themselves and escaped from the jaws of big 

 larvee, but not without some injury. On account of the precarious nature 

 of their food-supply the larvse often have to fast for long periods. In 

 order to get an idea of their capabilities in this direction, a number of 

 larvse were fed in the following manner : — 



On the 8th July 1912, 39 larvae hatched and until the 22nd July 1912, 

 aphides were supplied in large quantities every second or third day. On 

 the 24th July 1912, they were given number of silverfish. Food (silverfish) 

 was again supplied on the 14th August 1912, at which time many were 

 found dead. 



Food was again supplied on the 28th September 1912. On this date only 

 two larvse were found living. Only two silverfish were supplied and one 

 was seen to be caught and sucked by each of the two larvse. From this 

 date until the 20th April 1913, the two larvee were supplied with two silver- 

 fish at a time at intervals of twelve to fifteen days and care was taken to 

 see that each of tbem had one silverfish for its share. This could be done 

 by goading the silverfish to run over the extended jaws of the larva several 

 times. Sometimes it was caught the first time. In the course of about eight 

 months the two larvse fed on twenty silverfish of medium or big size. At 

 the end of March 1913, a calamity befell one of the larvse. It had caught 

 and sucked one silverfish but could not get rid of the dead skin which 

 stuck to one of the jaws. On the 6th April, the dead silverfish was wetted 

 with water and removed but the jaw was found disabled, being incapable 

 of movement and this larva appeared weaker than the other. Then on 10th 

 April the stronger larva attacked and sucked its weaker brother at night. 

 It was evident that they wanted more food. Henceforward the surviving 

 larva was always kept supplied with silverfish and it fed on the average on 

 two every day. Some time before pupating the larvse want to feed vora- 

 ciously, and if food is short they develop cannibalism and prey vipon each 

 other. On another occasion a larva, before pupating, deliberately attacked 

 and sucked another. In winter the larvae are not dormant. 



They have a peculiar way of shamming death. When they sit under the 

 dust with extended jaws they can be lifted by one jaw and they will not 

 make the slightest movement. If they are disturbed while walking they 

 draw in the head and legs and lie motionless. 



Pupa. — When full-grown the larva builds a cocoon (see plate, fig. 4) with 

 silk exuded from the anal end in the same manner as Crocejilipennis. In 

 the Insectary the cocoons were built on the wall of the cage just touching 

 the surface of the layer of dust in which the larvselived. A dull or yellow- 

 ish white silk is thrown out from the anal end and the larva turns 

 continually round and round, at the same time applying the silk to 

 particles of sand, pellets of earth or any foreign material which may be 

 near. The head with the jaws is either held raised and doubled over on to 

 the back or at times deflexed and doubled under the ventral surface, which- 

 ever is convenient at the time. The cocoon is completed in about 24 hours 

 and then the larva rests inside with the head doubled on the ventral surface. 

 The actual cocoon is about 9 to 11 mm. in diameter but looks bigger on account 

 of the pellets of earth, sand and other material which stick to its surface. 

 The pupa remains in a ventrally curved position inside the cocoon, the larval 

 skin lying as it was pushed off in the form of a crumpled mass at the end 

 of the abdomen. All the parts and limbs of the future imago are clearly 

 defined and free in the pupa. The wings are folded towards the ventral 

 surface. There is a pair of powerful jaws. 



Before the imago emerges the pupa partly comes out of the cocoon by 

 bursting it near the head. The pupa straightens its body at frequent 

 intervals thus striking the head against the cocoon in the bursting of 



