197 



spines on Ihe middle joint and with only a single one on the terminal joint; 

 inner ramus represented by a small joint carrying 2 slender setae. Ovisacs 

 confluent to a single almost globular bag attached to the dorsal face of the 

 genital segment. 



Male of about same size as female, and having the body more pro- 

 nouncedly club-shaped. Lateral lappets of 3rd trunkal segment comparatively 

 smaller. Tail with the genital segment considerably tumefied; anal segment 

 smaller than in female. Caudal rami scarcely at all divergent. Posterior 

 antennae still more strongly developed than in female, with the apical claw 

 much more produced. Posterior maxillipeds likewise more powerful, with the 

 propodos larger and the dactylus very long. 



Body in both sexes highly pellucid, and in some places tinged with 

 a light reddish orange pigment. 



Length of adult female about 1 mm. 



Remarks. This form was first described by Lubbock from specimens 

 captured at the west coast of England (Plymouth), and has subsequently also 

 been observed by several other authors, though its identity has not always 

 been recognised. Thus the C. germanus of Leuckart is unquestionably the 

 very same species. It is nearly allied to C. obtusus of Dana, but apparently 

 specifically distinct. 



Occurrence. I have met with this form occasionally off the west coast 

 of Norway, as also in the Christiania Fjord, at Drobak, among plankton taken 

 near the surface of the sea. It is, like the other species of this genus, a pro- 

 nouncedly pelagic animal, which has its true home in the open sea and only 

 quite accidentally is thrown by the currents nearer to the shores and into 

 the Fjords. 



Distribution. North Atlantic Ocean, off the British Isles (Lubbock & 

 Brady), Helgoland (Leuckart); coast of Bohuslan (Trybom). 



Fam. 14. Ergasilidae. 



General Characters. Body in the juvenile state of the animal quite 

 cyclopoid in shape, becoming however in the adult female, after its affixion, 

 more or less deformed. Eye simple, of normal appearance. Anterior antennae 

 comparatively short, resembling in structure those in the Corycceidce. Posterior 



26. Crustacea. 



