aoA-M. NATURAL HISTORY OF THE ISOPODA— RICHARDSON. 



S9 



Fig. 9. — Cymoddcka acuta. 



ft, ANTENN.E (IF TH K FIRST 

 pair; h, LABRIM. 



The tirst segment of the abdomen is twice as long as the last tho^ 

 racic segmont. There are three suture lines on either side, the first 

 pair being entirely eoneealed exeept in a lateral view. This segment 

 is posteriorly produced in two small points, one on either side of the 

 median line, and in two larger points, one on either side a little within 

 the line of the epimeral sutures of the thoracic 

 segments. The terminal abdominal segment 

 has a large triangular lobe within the notch at 

 __^^ the posterior extremity. The lobes 



=^ on either side of the median lobe are 



smaller and shorter. About the mid- 

 dle of the segment are two elevations, 

 one on either side of the median line, 

 transversely situated. The uropoda 



are equal in length, and are shorter than the terminal seg- 

 ment. J5oth are pointed posteriorly. The outer one is 

 more tapering than the inner one. which is equal in width 

 throughout its length. 

 FiG.io.— lat- The legs are all similar in shape and size and terminate in 

 OF BODY oT biunguiculate dactyli. They are ambulatory in character. 

 cymodocea Only one specimen was collected by the U. kS. Fish Com- 

 ■ mission steamer Alhatross at Yeno-Ura, .Japan. It was taken 

 on the surface. 



7}/i>.'.— Cat. No. 29084, U.S.N.M. 



This species differs from C. mammifera Haswell/' from Port Deni- 

 son, Queensland, in having the uropoda shorter than the terminal 

 segment, while in that species they are longer than the terminal seg- 

 ment; and in having the lateral angles of the thoracic segment drawn 

 out in acute processes, while in C. maunn/fi'i'd they are '"rather 

 blunt." 



VALVIFERA or IDOTEOIDEA. 



Family IDOTEID.E. 

 SYMMIUS, new genus. 



Head with lateral parts expanded; lateral margins entir(\ not cleft. 



Eyes small and situated on the posterior part of the expanded lateral 

 portions. 



First pair of antenna* elongate, consisting of four joints, the hist 

 joint being clavate. Second pair of antennie very short, not h)nger 

 than the tirst pair, and consisting of six joints, tive being peduncular, 

 th(> sixth joint b«>ing the flagellar joint. Maxilliix'ds witli a tlin'c- 

 jointed palp. 



Epimera prt^sent and developed on only the last three segments of 

 the thorax, as in GlyptonoUin Eights, the ei)iniei:i of the three ante- 



"Proc. Linn. Snc. Xi'w Sontli Walc.^^, V, ISSO, j.p. 474, \"^. 



