ISOPODS OF NORTH AMERICA. 



381 



FIG. 416. SYNIDOTEA NEBULOSA (AFTER 

 BENEDICT), x 3. 



SYNIDOTEA NEBULOSA Benedict. 



Synidotea nebulosa BENEDICT, Proc. Acad. Nat. Sci. Phila., 1897, pp. 397-399. 

 RICHARDSON, Proc. U. S. Nat. Mus., XXI, 1899, p. 848; Ann. Mag. Nat. Hist. 

 (7), IV, 1899, p. 268; American Naturalist, XXXIV, 1900, p. 227. 



Localities. Unalaska; Kyska Har- 

 bor; Semidi Islands; Unimak Island; 

 Bering Sea; Kamschatka; Constantino 

 Harbor, Alaska; East of Amak Island, 

 Alaska. 



Depth. 6 to 32 fathoms. 

 Body ovate, a little more than twice 

 as long as wide, 5mm. : 11 mm. Length 

 of abdomen a little more than one-third 

 the length of the entire body. 4 mm. : 11 

 mm. Head, first four segments of 

 thorax, and abdomen dark in color, the 

 surface being densely covered with 

 small black marks. The last three seg- 

 ments of the thorax are much lighter 

 in color, being a light brown with only 

 a few scattered markings of black. 



The front of the head is almost 

 straight, with only a very small median 



excavation. The anterior portion of the head is slightly narrower 

 than the posterior portion. The lateral margins are straight. The 

 eyes are large and round, composite in structure, and placed about 

 the middle of the head near the lateral margins. The first pair of 

 antenna? have the first and second articles about 

 equal in length, the first article not being dilated; the 

 third and fourth are subequal and each is about one 

 and a half times longer than the second. The first 

 antennae extend to the end of the fourth article of 

 the peduncle of the second pair of antennae. The 

 basal article of the second antennae is almost incon- 

 spicuous from a dorsal view; the second article is 

 short, not much longer than the first; the third is but 

 little longer than the second; the fourth and fifth 

 are subequal and each is twice as long as the third. 

 The flagellum consists of six articles. When retracted, the second 

 antennae extend to the posterior margin of the second thoracic seg- 

 ment. The maxilliped has a palp of three articles. 



The first four segments of the thorax are longer than the last three. 

 All the epimera of all the segments are firmly united with the seg- 

 ments. The lateral margins of the segments are somewhat rounded. 



FIG. 417. SYNIDOTEA 

 NEBULOSA. MAXIL- 

 LIPED. x 27}. 



