70 Journal New York Entomological Society. [Vol. xm. 



large maggots. However in most leaves numerous individuals of the 

 chironomid larva were present, indeed, they were often more abundant 

 than the larvae of Wyeomyia. In many leaves all three forms of larvae 

 were found associated. In some leaves the water was converted into 

 an extremely foul liquid, through the decay of large insects that had 

 been entrapped, and in such only the large maggot occurred. But 

 the chironomid larvae also can endure quite foul water, for in one case 

 they were numerous in a leaf in which had been drowned one of the 

 large Spirobolus marginatus . 



The chironomid was at once thought to be an unknown form and 

 received such attention as circumstances permitted. Some of the 

 larvae were reared and produced a little black fly which runs actively 

 but does not take flight so readily as most of its allies. Specimens of 

 the fly were sent to Mr. D. W. Coquillett and were described by him 

 as Metriocnemus knabi in the Canadian Entomologist, vol. 36, p. n. 

 The genus Metriocnemus had not previously been reported from the 

 North American continent, although it is a large and widely dis- 

 tributed one and species are known from Greenland and elsewhere in 

 the Arctic region, Europe, South America and Australia. Apparently 

 nothing has been made known regarding the early stages in this genus. 



The larvae of the present species live at the bottom of the water- 

 filled leaf-cups of Sarracenia purpurea, burrowing in the closely 

 packed debris composed of the fragments of decayed insects • evidently 

 their food is from this source. These larvae, unlike those of most 

 species of Chironomidae, make no tubes. Upon the first occasion 

 only larvae were found, but this is doubtless because the pupae were not 

 discovered in their unusual situation. Upon August 23 the locality 

 was visited again and this time pupae were found — in a most abnormal 

 situation for a chironomid. 



Upon the inner surface of the pitcher, just above the water level, 

 was a mass of a clear gelatinous substance, and within this the pupa 

 was suspended in a perpendicular position, head uppermost. Some- 

 times there were a number of these pupae in a row, each in its own 

 globule of jelly. When the larvae pupate close to each other the gel- 

 atine secreted by them forms a confluent mass. The jelly mass of an 

 isolated pupa is elongate, slightly flattened, and its lower end extends 

 slightly into the water. So transparent is the jelly that the lower sub- 

 merged end is scarcely visible, but its tip is indicated by a more opaque 

 portion, which is the cast off larval skin. By this contact with the 

 water the jelly mass is prevented from drying up before the imago can 



