supposition, that this form lead a parasitic life in the said fish. This is however 

 by no means the case. The Ostracods had simply attaked the Spinax when 

 hanging on the fishing line in a dead or feeble condition, and had entered 

 the most accessible openings of the fish in order to feed upon its soft parts. 

 The finding of allied Ostracods on the gills or other places on recently captured 

 fishes, as mentioned by some other authors, may be explained in a similar 

 manner. On the other hand, the present Ostracod itself is not seldom found to 

 be infested with a peculiar parasit, Cyproniscus cypridince, described in the 2nd 

 Volume of the present work. The parasit. is generally only found on female 

 specimens and occupies the place where otherwise the ova and embryos of 

 the Cypridina are carried during their developement. 



Distribution. West coast of Sweden (Skogsberg), Shetland Isles (Norman). 



2. Cypridina megalops, G. O. Sars. 

 (PI. IV). 



Cypridina megalops, G. O. Sars, Undersegelser over Hardangerfjordens Fauna. Chr- Vid. 



Selsk. Forh. 1871, pag. 278. 



Specific Characters. Female. Shell comparatively shorter and stouter 

 than in the preceding species, seen laterally, of a less regularly oval shape, 

 being considerably higher behind than in front, dorsal margin strongly arched 

 in its posterior part, but more slowly declining in front, ventral margin evenly 

 curved, posterior extremity bluntly rounded, with the lower corner but very 

 slightly exerted; seen dorsally or ventrally, ovale. in shape, with the greatest 

 width somewath behind the middle. Frontal incisure of the valves of a similar 

 shape to that in C. norvegica; defining angle below however less prominent, 

 and the rostral projection comparatively broader. Surface of shell smooth and 

 polished. Eyes of considerably larger size than in the female of C. norvegica 

 and very conspicuous in the living animal. Anterior lip with only slight traces 

 of lateral lappets. Inner ramus of posterior antennae very small and only 

 composed of 2 joints, distal joint knob-like and terminating in a very long 

 and slender seta. Terminal plate of posterior maxillipeds fringed with an 

 uninterrupted row of about 18 plumose setae. Caudal lamellae each armed 

 with 11 claws. Structural details otherwise very little different from those in 

 C. norvegica. 



Male rather like the female in its outward appearance, but slightly larger, 

 and having the posterior part of the shell less broad and somewhat more ex- 



2 Crustacea. 



