ISOPODS OF NORTH AMERICA. 



259 



iJS mill., widest at 



111111. : 5 



Body ovate, not twice as wide as long, IT mm. 

 the fourth thoracic seo-ment. 



The head is triang-uhir, and at the base is wider than loiio 

 mm.; it is partly set in the first thoracic seg-- 

 ment, the antero-Iateral angles of which extend 

 to about the middle of the head. The eyes are 

 small, oval, composite, situated in the post- 

 hiteral angles of the head, and separated ante- 

 riorly b}" a distance nearlv equal to the length 

 of one e3^e. The posterior margin of the head 

 is rounded; the anterior margin is widely 

 rounded. The anterior end is 2 mm. wide. 

 The first pair of antennae are composed of eight 

 articles and extend to the end of the sixth article 

 of the second pair of antenna\ The basal arti- 

 cles are not adjacent, being separated by a dis- 

 tance equal to 1 mm. The second pair of an- fig. 2G8.— livoneca vri/i.v- 



, jiii-i'i ii.j Ris (After Stimpson). 



tennte are composed or ten articles, and extend ' 



to the middle of the first thoracic segment. The maxillipeds have a 



Fig. 269.— Livoneca vulgaris, a, Maxilliped of female, x 27j. b, Seventh leg. x 9|. c, 

 Second maxilla, x 27}. d, First maxilla, x 27j. e, Palp of mandible, x 27j. 



palp of two articles. The palp of the mandibles is composed of three 

 articles. 



The first and fourth segments of the thorax are the longest, each 

 being 3 mm. in length. The second and sixth are each 2 mm. long. 



