166 The Ohio Journal of Science [Vol. XXI, No. 5, 



Bidessus lacustris Say. One specimen was taken. 



Hydroporus modestus Aube. This fairly common beetle 

 was about as numerous as L. macidosiis. Practically all were 

 from station 3. 



Hydroporus concinnus Lee, was evidently rare as only 

 one specimen was found. 



Hydroporus pulcher Lee, was likewise rare with only one 

 specimen found. 



Hydroporus dichrous Melsh. probably must also be consid- 

 , ered rare, as only two specimens were found. 



Copelatus glyphicus Say.* This beetle of which only two 

 specimens were found, was in the same general situation as 

 Hydroporus. One of the specimens is piceous and the other 

 slightly reddish. 



Family GyrinidcE. 



This family was conspicuous by its absence. The writer 

 can say with assurance that none were present during the 

 period collections were made, though there were reports that 

 whirligig beetles were present a few years before. The Lemna 

 covered small pond would be very unfavorable for their gyra- 

 tions, though the large pond presented no such difficulties. 

 Possibly the absence of favorable aquatic plants for egg deposi- 

 tion was an important factor. Fishes, if they had any effect, 

 would have relatively less upon these than upon other beetles. 



Family Ilydrophilidce. 



The beetles comprising this family were about equal in 

 number of species to the Dytiscidas, but more numerous in 

 individuals, due chiefly to the abundance of a few common 

 kinds. A considerable number of larvae were obtained. 



Helophorus lineatus Say. This species was found quite 

 common but only at stations 3 and 11. They were usually 

 noticed crawling on submerged vegetation. 



Hydrochus inaequalis Lee. This beetle, found in about the 

 same situation as the preceding, must be rated as rare. 



Ochthebius nitidus Lee. (?)t Of this beetle' also only one 

 specimen was found, so that it must be rated as rare. It was 

 found in vegetation at the very edge of the pond at station 3. 



* Identified by C. W. Leng and H. C. Fall. 



t Identified as probably this by Mr. C. W. Leng. 



