238 BIOLOGICAL SUEVEY OF 



ships within the genus. Further, the as yet unselected type 

 is a Cretaceous species, so that we shall in all probability 

 never know the appendages of the type and I quite agree 

 with Skogsberg that a knowledge of the appendages is very 

 necessary to the discrimination of subgenera m Cythereis. 

 Skogsberg (1928), in the second part of his studies, has given 

 a valuable discussion of this genus and its internal divisions 

 as he conceives them. Unfortunately, I do not find myself 

 able to agree with him on certain points. 



As far as we are concerned here, the most important dis- 

 agreement is with the subgenus Cythereis which he sets up 

 on page 38. Skogsberg fails to show that it includes any 

 of Jones' original species, and on his own showing (p. 16), 

 I think it is virtually impossible for us ever to be sure to 

 what subgenus any of Jones' species belong. Hence, to avoid 

 nomenclatorial difficulties, the subgenus in question should 

 have received a distinct name from that of the genus. It 

 may be remarked at this point that, through correspondence 

 with Dr. Charles I. Alexander, I have been convinced that 

 certain of Jones' species are congeneric with the genus 

 Cythereis as conceived by G. W. Miiller and Skogsberg. 



Further, a careful comparison of Skogsberg 's subgeneric 

 descriptions with the descriptions of Hemicythere and Cy- 

 thereis as given by G. 0. Sars (1925, pp. 182, 191, and plates) 

 shows clearly that the former genus must be withdrawn or 

 at least reduced to the rank of a subgenus of Cythereis. 



As far as the present list is concerned, Hemicythere is 

 treated as a subgenus, as also a small and well-characterized 

 group of winged species. The remaining species are placed 

 without subgeneric discrimination. 



C. DUNELMENsis Normau. (G. 0. Sars, 1925, p. 195, pi. 90.) 

 Taken once on rock, in 30 feet of water, at D 35. 



C. DAWsoNi (Brady). (Cushman, 1906, p. 372, pi. 35, tigs. 

 84, 85.) The sculpture of this species has a curious and char- 

 acteristic eroded appearance. Limbs 5 to 7 of the male are 

 slightly unlike on the two sides. Taken on mud bottom in 

 10 to 70 feet of water. Stations : J) 46, 59. 



