ISOPODS OF NOETH AMEEICA. 229 



ANILOCRA PLEBIA Schicedte and Meinert. 



AnUocra plebia SCHICEDTE and MEINERT, Naturhistorisk Tidsskrift (3), XIII, 

 1881-1883, pp. 145-146, pi. x, fig. 3. RICHARDSON, Proc. U. S. Nat. Mus., 

 XXIII, 1901, p. 528. 



Localities. Shores of Costa Rica; Central America. 



Body elliptical, two or three times longer than wide (9:4). Head 

 moderately large, subtriangular, one-third as wide as the fourth 

 thoracic .segment, much wider than long, very slightly immersed, the 

 front rounded in a circle. 



Eyes small, suboval, tumid, separated by a distance of more than 

 half the width of the head. 



The first pair of antennae are straight, rather compressed, and 

 extend with the two last articles to thie anterior angle of the first 

 thoracic segment and to the sixth article of the 

 second pair of antenna; they are composed of eight 

 articles. 



The second pair of antennae are rather com- 

 pressed, are a little narrower than the first pair 

 of antennae, and do not reach the posterior angle 

 of the first thoracic segment; they are composed of 

 nine articles. 



The anterior margin of the first thoracic seg- 

 ment is manifestly trisinuated, the lateral sinuses 

 being scarcely deeper than the median sinus. 



, . FIG. 232. ANILOCRA 



Ihe posterior angles of the first six segments of PLEBIA (AFTER SCHI- 

 the thorax are scarcely or not at all produced, <**"* AND MEINERT). 



. ' YOUNG FEMALE. (EN- 



bemg rounded or obtuse. Ihe posterior angles of LARGED.) 



the seventh segment are a little more produced and 



rounded. The angles of the seventh segment do not reach by a small 



distance the posterior angle of the first segment of the abdomen. 



The epimera are projecting. The first three are rather wide or 

 rather narrow, decreasing gradually in width, with the posterior mar- 

 gin widely rounded. The three posterior ones are narrow, subequal 

 in width, with the posterior margin narrowly rounded. The epimera 

 of the first and second pairs extend almost to the posterior angle of 

 the segment; those of the third pair do not reach by a small distance 

 the posterior angle of the segment; the fourth, fifth, and sixth pairs 

 of epimera are subequal and do not reach by a large distance the pos- 

 terior angle of the segment. 



The first six pairs of legs gradually increase a little in length; those 

 of the last parr are manifestly longer and a little more slender than the 

 others. The ungulse of the first pair are rather long and rather stout; 

 those of the second, third, fourth, and fifth pairs are long or ver} 7 long, 

 rather stout, subequal in length; those of the sixth pair are long or 



