40 "''III- CANADIAN' ENTOMOLOGIST 



are irregular in shape, larger on some segments than others. The 

 seventh and eighth abdominal segments are light yellowish brown 

 in colour. Each segment bears a fringe of setae on its posterior 

 margin, while numerous smaller setae are scattered over their dorsal 

 surfaces. The setae constituting the fringe are much shorter than 

 the segments. The cerci consist of two long, slender, two-jointed 

 appendages. They are 2 mm. long, much longer than the seventh 

 and eighth abdominal segments taken together. The 1st segment 

 measures 1.2 mm., while the long seta-like terminal joint measures 

 .8 mm. The basal segment is studded with numerous small setae. 

 Three long, fine setae arise at the distal end of each basal seg- 

 ment, and are about half as long as the second segment of 

 the cerci. 



The legs are almost white in colour. The coxae are shorter 

 than the femora. The femora and tibia are armed with stout 

 spines on their ventral surfaces. There are but few setae on the 

 tarsi and swimming fringes are lacking. The tarsal claws are 

 long and sharp. 



The pupa 



The pupa is pure white in colour, except the eyes, which are 

 black. It rests upon its back in the pupal chamber. Length 

 3.5 mm. The head lies incurved upon the presternum, and is 

 rather abundantly provided with strong, short setae, which 

 prevent the tender pupa from coming in contact with the fine 

 sand grains. The anterior margin of the pronotum is provided 

 with a row of strong setae, while numerous smaller setae are present 

 on the dorsal side of all the thoracic segments. The posterior 

 margin of each abdominal segment is considerably elevated and 

 is provided with a row of strong setae. The abdomen ends in a 

 pair of large ventral spines measuring .5 mm. By the aid of these 

 spines the pupa is enabled to move about in. the chamber, and at 

 the same time prevent injuring itself from coming in contact with 

 the small grains of sand. I do not know how long the pupal 

 period lasts, but not more than a week or ten days. 



The adult is a rather prettily-marked beetle, and is repre- 

 sented in fig. 5. 



