62 Bulletin American Museum of Natural History [Vol. XLII 



Formerly this genus was united with Philydrus and it closely ap- 

 proaches it. Helochares, however, may be easily distinguished in the 

 field by the punctures of the elytra, which are arranged in rows. In 

 general form, it is more like Helocombus, but this genus" possesses longer 

 maxillary palpi and its elytra are distinctly striate. 



Cussac, 1852, described the immature stages but his work was not 

 very carefully done. The full-grown larva was figured as well as the 

 pupa. The latter, however, was destroyed before the drawing was 

 finished, with the result that the caudal end was not accurately com- 

 pleted. D'Orchymont, 1913, acting on Ganglbauer's suggestion for a 

 more accurate description of the European species, H. lividus, gave an 

 excellent description of the larva and supplemented it with figures. 



Helochares maculicollis Mulsant 

 Plate XIII 



I am deeply indebted to Mr. F. E. Wintersteiner for the oppor- 

 tunity of rearing H. maculicollis. On April 12, 1916, I received ten 

 living adults which he had forwarded to me from Richmond, Virginia. 

 They were apparently in good condition, although a number of mites 

 were attached to them on the under side. The specimens had been col- 

 lected at the edge of leaf-filled pools a few days previous to their ship- 

 ment. 



When placed in the rearing jar, they immediately became submerged 

 and remained on the under side of some stones or burrowed down in the 

 mud. Although on sunny warm days they would be seen swimming 

 about the jar, yet most of their time was spent in hiding. Because of 

 this fact, it was difficult to observe whether or not the females carried 

 any cases as they were reported to do. 



On June 4 the container was flooded and soon a number of young- 

 larvae were noted floating on the surface and crawling around the edge 

 of the glass. Later in the day two females were seen swimming at the 

 surface of the water, right side up, each with an egg-case slightly protru- 

 ding caudally. 



The egg-case was attached by two strands to the hind femora and 

 not free as Schiodte describes it in lividus. The beetles could swim with 

 little incumbrance. Both cases hatched out two days later and forty- 

 six and forty-two larva? appeared from the respective cases. Other 

 cases were observed during the first week in July and a single case as 

 late as September 2-1. The latter case hatched on the 29th. The larva? 



