130 



12. CHiETARTHRiA, Waterhouse. 



Hydrophilus Seminulum of Paykull is the type 

 of this genus, which was first separated from Hy- 

 drobius by the above writer ; Erichson, in the 

 Kafer den Mark Brandenburg, has given the generic 

 name of Cyllidium to the same species ; the latter 

 name of course falls. Vid. page 211 of the last 

 quoted work for the generic details, &c. &c. 



LINNEAN AQUATICS— continued. 



Sp. 6. Latissimus. — Now a Dyticus, and the type 

 of the genus. The following families, according to 

 my views, belong to the Dyticoidea, viz. Haliplidse, 

 Dyticidae, and Gyrinidse ; the genera belonging to 

 the family of Dyticidae are as follows : 



