ISOPODS OF NORTH AMERICA. 



303 



FIG. 325. DYNAMENE 

 MOOREI (AFTER 

 MOORE). 



DYNAMENE MOOREI, new species. 



Dynamene perforata MOORE (female), Bull. U. S. Fish Commission, XX, Pt. 2, 

 1902, pp. 173-174, pi. x, fig. 10. RICHARDSON (female), Trans. Conn. Acad. 

 Sci., XI, 1902, pp. 291-292. 



Localities. Culebra, Porto Rico; Bermudas. 

 Found on mangrove roots. 



This species is what Dr. Moore considered to be the female of 

 Dynamene perforata. Upon examining the specimens 

 of Dynamene perforata (females) I found one to be a 

 male. a 



Body oblong-ovate, about twice- as long as wide, 2 

 .mm.: 4 mm. 



Head about twice as wide as long, with the frontal 

 margin rounded and produced in a small median point. 

 Eyes large, composite, and situated in the post-lateral 

 angles of the head. First pair of antennae have the 

 first and third articles of the peduncle about equal in 

 length ; the second shorter than either. The flagellum 

 of eight articles extends to the posterior margin of the first thoracic 

 segment. The second pair of antennae, with a flagellum of twelve arti- 

 cles, extends to the posterior margin of the 

 second thoracic segment. 



The first segment of the thorax is about 

 one and a half times longer than any of the 

 following segments, which are subequal. 

 The seventh segment is produced backward 

 in two small, rather obscure points, close to- 

 gether, one on either side of the median line. 

 The abdomen is composed of two segments. 

 The second or terminal segment bears four 

 small, rather obscure tubercles on the an- 

 terior convex portion. This segment is some- 

 what triangular in shape, with the apex 

 notched and the sides folded under, forming a 

 kind of funnel-shaped extremity. 

 The uropoda are large and broad, similar in shape and size, with the 

 extremities rounded and the exterior margins crenulate. They extend 

 but little beyond the extremity of the abdomen. 



Both sexes of this species are known, the males and females being 

 similar. 



This species is named for Dr. H. F. Moore. 



Since my manuscript was sent to press, Doctor Hansen has returned specimens 

 of Dynamene perforata Moore, which he borrowed from the U. S. National Museum. 

 Two specimens, considered by Dr. H. F. Moore to be the females of that species, 

 were sent him. I am gratified to find that he has labeled one "immature male," 

 and the other "adult male." . 



FIG. 326. DYNAMENE MOOREI. 

 SECOND PLEOPOD OK MALE. 

 x 77i. 



