442 



BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



mer without dorsal plates, the latter without ventral lobes, and twice 

 as wide as long; legs enlarged but little, the rami 1-segmented. A 

 single species in the area. 



CECROPS LATREILLII Leach 



Figure 278 



Cecrops latreillii Leach, Supplement Encyclopaedia Britannica, vol. 1, p. 405, 

 pi. 20, figs. 1-5, 1816.— WILSON, Proc. U. S. Nat. Mus., vol. 33, p. 468, pis. 

 38, 39, 1907. 



Occitrrence. — Found on the gills of the common sunfish captured 

 in the pound nets on Marthas Vinej^ard. 



Distribution. — British seas (Allman, Thompson, A. and T, Scott, 

 Norman) ; New Zealand (Thomson) ; Mediterranean (Hope, Heller, 

 Valle, Carus) ; Nizza (Risso) ; Norway (Olsson, Kr0yer) ; northern 



Pacific, Gulf of Maine 

 (Brian) ; coast of 

 Belgium (Hoeven) ; 

 off Gay Head (S. I. 

 Smith, Rathbun). 



Color. — Body a uni- 

 form yellowish white, 

 the anterior ventral 

 surface of the abdo- 

 men, and the edges of 

 the dorsal plates of 

 the genital segment 

 with a few spots of 

 light-brown pigment, 

 very irregularly ar- 

 ranged; egg strings a 

 deep orange-brown, 

 the color increasing 

 with development. 

 Female. — The division between the head and first segment is indi- 

 cated by a notch on each lateral margin of the carapace, and by a 

 dorsal groove across the lateral area. The broad lateral plates of 

 the second segment are concealed beneath the posterior lobes of the 

 carapace; the small median plates of the third segment overlap 

 slightly those of the fourth segment, and the latter are triangular 

 and reach the center of the plates covering the genital segment, 

 being longest on the midline. The plates of the genital segment 

 are nearly twice the length of the carapace, their margins are 

 softened and rolled over ventrally, completely inclosing the abdomen, 

 caudal rami, and ^^g strings; caudal rami small, orbicular, and 

 armed with spines only. Total length, 25-30 mm. 



-Cecrops latreillii: a. Female, dorsal; 6, 

 male, dorsal 



