ISOPODS OF NORTH AMERICA. 



437 



segment, al)oiit one-litill' its k;ii<;tli. The piHluncle is about as lon^- as 

 the inner branch. The outer branch is about one-fourth shorter than 

 the inner branch. 



The tirst pair of leg's are subcluihite. The propodus is armed on the 

 inferior margin with a triangular process near the distal end and with 

 a long spine at the proximal extremity. The dactylus is armed with 

 numerous spines along the inferior margin. All the other legs are 

 ambulartory, with dactyli uni-unguiculate. 



CJE.CIDOTKA RICHARDSONiE Hay. 



Ciecldotea richardsonte Hay, Proc. Biol. Soc. Washington, XIV, 1901, pp. 179-180; 

 Proc. U. S. Nat. Mus., XXY, 1903, pp. 424-428. 



Locality. — Nickajack Cave, Tennessee. 



Bod}^ narrow, elongate, four and a half times iongcM* than wide, 2 

 mm. : 9 mm. 



Head a little wider than long, with the antei'ior margin slightly 

 excavate. Sides of head 

 e n ti re . Ey es wanting. 

 The first pair of antennae 

 have the first article about 

 twice as long as wide; .the 

 second article is as long as 

 the first, but half as wide; 

 the third article is one- 

 third the length of the sec- 

 ond; the flagellum is com- 

 posed of eleven articles 

 and extends one-third the 

 length of the fifth article 

 of the peduncle of the sec- 

 ond pair of antennte. The 

 second pair of antenna' 

 have the first two articles 

 equal in length; the third 

 article is about half the 

 length of the second; the 

 fourth is as long as the 

 first three together; the 

 fifth is one and a lialf times 

 as long as the fourth. The 

 fiagellum is composed of 

 about eighty-six articles. 



bod3\ The maxillij)eds have a palp of five article 

 mandibles is composed of three articles. 



The first four segments of the thorax are subequal in length. The 

 fifth is a little shorter. The sixth and seventh ar<^ subecjual and each 



Fk;. 495.— C.kcidotka itiCHARDSON.E (AFTER Hay). a, Dor- 

 sal VIEW. X (i. 6, First ANTENNA, r, Second antenna. 



'/, MaNDIBLK. I. FlK.ST MAXII.I.A. J. SECOM) MAXILLA. 

 //, MaXII.LIPEI). ('/. ['PPEK LIP. /. LoWER LIP. j. GNATH- 

 ()P()I>. 



The second antenna' ai'c longer than the 



The palp of the 



