344 



BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



He also found it would live and reproduce as well in mineral water 

 as in fresh water. 



Family CLAUSIDIIDAE 

 Genus CLAUSIDIUM Kossmann, 1875 



Female. — Body short, broad, and strongly flattened; head fused 

 with first segment, second and third segments free ; fourth and fifth 

 segments fused and covered with a single plate; no eye visible. 

 Urosome 3- or 4-segmented; genital segment widened but little; 

 caudal rami longer than wide, each tipped with two setae. First 

 antennae 7-segmented; second antennae 3-segmented, nonprehensile, 

 tipped with long setae. First four pairs of legs biramose, rami 

 3-segmented ; fifth legs uniramose, 1-segmented, 



Male. — Body elongate, slender, flattened; head fused with first 

 segment, the other segments free; fourth and fifth segments sepa- 

 rated, but the dorsal plate of the fourth segment overlaps the base 

 of the fifth segment. Urosome 5-segmented; genital segment di- 

 vided, with a pair of spines at the posterior corners; caudal rami 

 longer than wide, each armed with four setae. Appendages like 

 those of the female except the maxillipeds, which are subchelate. A 

 single species. 



CLAUSroiUM DISSIMILE Wilson 



Figure 205 



Glausidium dissimile Wilson, Proc. U. S. Nat. Mus. vol. 59, p. 427, pis. 94, 95, 

 1921. 



OcctKri'ence. — Two males and two females from branchial cham- 

 ber of CalUanassa stimpsoni Smith, captured in Vineyard Sound, 



September 2, 1901; 25 specimens, 

 including both sexes, from bran- 

 chial chamber of C aZlianassa species 

 (probably stimpsoni) at Cold 

 Spring Harbor, Long Island, N. Y. 

 Distribution. — Found only in the 

 two localities just mentioned, but it 

 is likely to occur wherever CalUan- 

 assa crabs can be secured. 



Color. — Body a bright red, deep- 

 est along the margins of the seg- 

 ments. 



Female. — Cephalic segment twice 

 as wide as long, its posterior 

 corners produced backward; second and third segments as wide as 

 the head, with lateral epimeral plates ; dorsal plate of fused fourth 

 and fifth segments covering the basal segments of the fourth and 

 fifth legs and part of the genital segment; caudal rami one-half 

 longer than wide, in contact at their tips. Second segment of first 



Figure 205. — Clausidium dissimile: a. 

 Female, dorsal ; b, female, fifth leg ; 

 c, male, fifth leg 



