354 BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



The lateral margins of the head are cleft, the anterior lobe being 

 smaller than the posterior, which projects at the sides beyond the 

 anterior one. The front of the head is not excavate between the 

 antero-lateral lobes, but on the contrary is expanded beyond them. 

 There is a pronounced median excavation, in the center of which is a 

 median point. The eyes are small, round, compound in structure, 

 dorsally placed at the base of the post-lateral lobe. The first antennas 

 have the basal article very short and not dilated; second article a little 

 longer than the first; third and fourth equal in length and each about 

 twice as long as the first. The first antenna? extend a little beyond 

 the end of the peduncle of the second antennae. The basal article of 

 the second antennae is inconspicuous from a dorsal view; the second, 

 third, and fourth articles are subequal; the fifth is a little longer than 

 the fourth. The flagellum consists of five articles. When retracted, 

 the second antennae reach the anterior margin of the first thoracic 

 segment. The maxillipeds have a palp of three articles. 



The segments of the thorax are equal in length. The epimera are 

 separated dorsally from the first three segments, but are not acutely 

 produced posteriorly. The epimera of the last four segments are also 

 distinct, and are produced into acutely pointed processes. 



The first three pairs of legs are subchelate, with propodus expanded, 

 the dactylus short and refiexed. The last four pairs of legs are ambu- 

 latory. All the legs are thickly beset with spines and hairs along the 

 free margins. 



The abdomen is composed of four segments, three short ones fol- 

 lowed by a long-pointed terminal one, with lateral sutures of another 

 partly coalesced segment. The apex of the terminal segment is acute 

 and its lateral margins near the extremity are denticulate. The sides 

 of the abdomen taper gradually to about the middle and then converge 

 more rapidly to the apex, forming slight angles on either side half way 

 from the base to the apex. 



The opercular valves are in two parts, the small terminal part rep- 

 resenting the outer branch of the uropoda. The inner branch is rep- 

 resented on the under side attached to the basal portion on the exterior 

 side. 



CHIRIDOTEA TUFTSII (Stimpson). 



Idotea tuftsii STIMPSON, Smithsonian Contributions to Knowledge, VI, 1853, p. 

 39. HARGER with VERRILL, Report U. S. Commissioner of Fish and Fisher- 

 ies, Pt. 1, 1873, p. 340 (46); p. 569 (275). VERRILL, Proc. Amer. Assoc., 

 1874, p. 362. 



Chiridotea tuftm HARGER, Am. Jour. Sci., XV, 1878, p. 374; Proc. U. S. Nat. 

 Mus., II, 1879,' p. 159; Report U. S. Commissioner of Fish and Fisheries, 

 Pt. 6, 1880, pp. 340-341, pis. iv, figs. 20-23. 



Glyptonotus tuftm MIERS, Jour. Linn. Soc. London, XVI, 1883, pp. 18-19. 



Chiridotea tuft Kit RICHARDSON, American Naturalist, XXXIV, 1900, p. 226; Proc. 

 U. S. Nat. Mus., XXIII, 1901, p. 539. 



