6 ARKIV FÖR ZOOLOGI. BAND 14. N:0 10. 



a pair of rudimentary dorsal plates, widely separated. Geni- 

 tal segment a little more than half the width of the carapace, 

 with straight lateral margins and well roiinded posterior 

 corners. Posterior sinus nearly one-third the width of the 

 genital segment, and showing the whole abdomen in dorsal 

 view. The anal laminae are relatively larger than in the 

 adult and are furnished with mueh longer setae, which are 

 plumose. Appendages and color the same as those of the 

 adult. 



Total length 3. 40 mm. Carapace I.90 mm. long, l.so 

 mm. wide. Genital segment O.90 mm. long, 1 mm. wide. 



Remarks. This new species differs from those hitherto 

 described rather by an accumulation of lesser details than 

 by any one prominent character. The complete closing of 

 the posterior sinus of the geni tal segment is perhaps the 

 most evident character. To this may be added the wicked 

 tooth-barbs of the second antennae, the form and armature 

 of the first maxillae, and the details of the swimming legs. 

 In this species also the process opposite the terminal claw 

 of the maxillipeds is as long as the claw itself. 



Taeniacaiitlius coelus New Species. Pl. 3, figs. 18—26. 



Hest and record of specimens. Thirty females, most of 

 them with egg cases, were obtained from an unknown höst, 

 probably an elasmobranchian fish, at Fujita's Colony, Misaki, 

 Japan, May 28, 1914. 



Many of them are still attached to soft epithelium appa- 

 rently from the nasal cavity, in which they are partly buried. 

 They do not, however, burrow at all into the tissue, but the 

 soft folds rise up around their bodies, partly enveloping 

 them. They attach themselves by drawing a fold of the 

 soft skin into the cavity of the front of the cephalothorax 

 and fastening into it the claws of the maxillipeds. 



Specific characters of the female. General body form 

 elongate and narrow, but with the abdomen relatively wider 

 than in other species. Cephalothorax inclined ventrally at 

 an angle of about 45 degrees to the body axis, the front 

 squarely truncated and forming a slightly projecting margin 



