1914.] 



NATURAL SCIENCES OF PHILADELPHIA. 



33 



C. fuscus may be readily distinguished from all other members 

 of the genus by its size, dark color, and closely Ij^ing dark egg-sacs- 

 The absence of the sense-club of the twelfth antennal segment, the 

 coarsely serrated hyaline plate of the seventeenth antennal segment, 

 the form of the receptacidum seminis, and the ciliated inner border 

 of the stylets are the most easily distinguishable characteristics of 

 this species. In order to simplify the comparison of C. fuscus with 

 C. albidus, I have arranged the following tabulated form for the 

 characters of the two species: 



Schmeil notes differences in the form of the spermatozoa and 

 their position in the spermatophore. The twelve points of difference 

 noted above should enable anyone to distinguisli the two forms 

 positively. 



