NO. 1894. 



ISOPODS FROM JAMAICA— RICHARDSON. 



191 



Family SPILEROMIME. 



EXOSPH^ROMA CRENULATUM (Richardson). 



Sphsetomacrenulatum Richardson, Trans. Conn. Acad. Sci., vol. 11, 1902, pp. 292- 

 293, pi. 39, fig. 40; Bull. U. S. Nat. Mus., No. 54, 1905, p. 298. 



Locality. — Montego Bay; 2 specimens; living on the outside of a 

 chiton. (Collected by C. B. Wilson.) 



EXOSPHjEROMA ANTILLENSE, new species. 



Body contractile, able to roll into a complete ball; surface reticu- 

 late; color yellow, with a few scattered spots of brown; on the head 

 are three arcuate patches of brown; on the first segment there is a 

 transverse band of brown about the middle of the segment; on the 

 second segment are two small transversely elongated patches of 

 brown on either side of the median line situated close together; on 

 the fourth segment are four patches, two 

 on either side of the median line, the two 

 middle ones being far apart; on the fifth, 

 sixth, and seventh segments are two patches 

 on each segment, one on either side of the 

 median line; on the first abdominal seg- 

 ment are two patches in longitudinal series 

 on either side of the median line and three 

 patches in longitudinal series on the lateral 

 parts of the segment; on the terminal ab- 

 dominal segment are two patches, one on 

 either side of the median line, situated 

 close together. 



The head is wider than long and has the 

 front produced in a small median point. 

 The eyes are small, composite, more or 

 less ovate with the upper end produced 

 angularly, and situated in the post-lateral 

 angles of the head. The first pair of antennae have the first article 

 large, and elongate, about twice as long as wide; the second article 

 is small and rounded, and is about one-third the length of the 

 first article; the third article is narrow, elongate, and is about one- 

 and-a-half times the length of the second article; the flagellum, com- 

 posed of eleven articles, extends about two- thirds the length of the 

 lateral margin of the first thoracic segment. The second antennae, 

 with a flagellum composed of twelve articles, extend to the posterior 

 margin of the third thoracic segment. 



The first segment of the thorax is a little longer than any of those 

 following and has the post-lateral angles produced backward and the 

 antero-lateral angles produced forward on either side of the head. 

 The following six segments are subequal. 



Fig. 1.— EXOSPEUEROMA ANTILLENSE. 



X 8§. 



