ISOPODS 



227 



Family TRICHONISCIDJE. 

 TRICHONISCUS PAPILLICORNIS sp. no/. 



Type from Seldovia, Cook Inlet, Alaska. 



Body covered with low tubercles. Color light brown. 



Head with sides produced at the antero-lateral angles in large lobes ; 

 front triangularly produced with 

 a slight emargination at the apex 

 of the triangle. Eyes situated 

 on the lateral margins at the base 

 of the antero-lateral lobes ; they 

 are small and black and appa- 

 rently simple in structure. The 

 peduncle of the antennae consists 

 of five stout joints, the last three 

 of which have the inner margins 

 beset with numerous strong tu- 

 bercular-like papillae, each sur- 



FlG. 113. Head and first thoracic segment of 

 TricJwniscus papillicorftis (X 4i)- 



mounted with a tuft of short stiff hairs or bris- 

 tles; the fifth joint is also produced at the 

 outer distal angle in an acute process. The 

 flagellum is composed of about seven joints, 

 the joints being rather indistinctly defined ; the 

 last joint is tipped with a bunch of hairs. The 

 buccal mass is very prominent below. 



The segments of the thorax are about equal 

 in length. The post-lateral angles of all the seg- 

 ments, except the first, are produced backward, 

 very slightly in 

 the case of the 

 second, third, 

 and fourth, but 

 becoming grad- 

 ually more so, 

 until the last 

 two segments 

 show this char- 

 acter very mark- 

 edly. 



The abdomen is narrower than the thorax. All the segments are 

 visible in entirety, not being covered laterally by the last thoracic seg- 



FlG. 



114. Trichoniscus papilli- 

 corm's sp. nov. (X 23). 



Fig. 113. Uropoda and last segment 

 of abdomen (X 77) • 



