188 THE CANADIAN ENTOMOLOGIST. 



dorsal side. The seven pairs of spiracles are prominent, all except 

 the third pair being black at the tip. The eyes are prominent 

 and somewhat blackish. The legs and wing-pads are held in 

 position as shown in fig 4 (ventral view of the pupa in position in 

 the larval skin). 



Stenelmis bicarinatus Lee. 



This species is quite common in Salmon River and I was not 

 surprised to find the larvae and pupae under stones along the banks. 

 Unfortunately, however, it was rather difficult to determine the 

 larva or pupa of this species as quite a number of other species of 

 Coleoptera were not uncommon in similar situations. However, 

 I found a considerable number of larvae transforming and many 

 pupae, one of which I reared so that I was able to definitely con- 

 nect all the different stages. The larvae leave the water about the 

 last of July or the first of August and construct small, smooth, 

 pupal chambers in damp situations under stones. I found many 

 pupae and a number of larvae in such situations about August 7, 

 1913. The beetle reared from one of these pupae emerged on Aug. 

 10th. Further than this I know nothing of the life-cycle of this 

 species, but this note may throw a little light on this small 

 family of interesting forms. 



The larva (fig. 6). The mature larva, ready to pupate, 

 measures 6.25 mm. long, and 1 mm. wide at its broadest part. It 

 is heavily chitinized, reddish brown in colour, the head and term- 

 inal segment of the abdomen being almost black. 



The head is small and the mouth parts very inconspicuous. 

 The antennae are three-jointed, yellowish brown in colour, 1st 

 segment measures .05mm., 2nd .09 mm.; the third, consisting of 

 two very small segments lying side by side, .027 mm. 



The larva consists of 12 segments exclusive of the head. The 

 last abdominal segment is longer than the two preceding segments 

 and ends in two sharp, short spines with two rounded lobes 

 between (fig. 6). The entire cuticle is densely covered with small, 

 dark elevations, each bearing a very minute spine. Otherwise, 

 there are no distinctive markings. The legs are short, well devel- 

 oped and suited for clinging closely to stones or other objects in 

 swiftly flowing streams. 



The pupa (fig. 7). The pupa is soft, white in colour, the 



