180 CALIFORNIA ACADEMY OF SCIENCES. 



Genus Hippolysmata Stimpson. 



Carapace furnislied with au elongated, compressed, dentate rostrum 

 which is nearly horizontal. Antennules furnished with two long flagella. 

 Mandibles strongly incurved, devoid of a palp, the apex undivided. Max- 

 illipeds elongated, furnished with an exognath, and an epipodite, the ter- 

 minal joint slender. First four pairs of pereopods furnished with an 

 epipodite; the first pair is a little stouter than the others and chelate, the 

 hand oblong; second pair filiform, multiarticulate and chelate. Abdomen 

 smooth above. 



Type. — H. vittata Stimpson. 



Kingsley in his Revision of the Genera of Crangon- 

 idse, Atyidae and Palsemonidse ^ states, in defining this 

 genus, that the first four pairs of feet are provided with 

 an exopodite. This is probably a clerical error, the 

 word exopodite having been substituted for epipodite. 

 Stimpson says in his definition of this genus: '' Pedes 

 1 nii-4 ti epipodo instructi.^' ^ 



Hippolysmata calif ornica St. 



Hippolysmata californica Stimpson, Troc. Chicago Acad. Sci., Vol. I, 1866, 

 p. 48; Ann. N. Y. Lye. Nat. Hist., Vol. X, 1873, p. 123. Kingsley, 

 Bull. Essex Inst., Vol. X, 1878, p. 56. 



Hippolyte lineata Lockington, Proc. Cal. Acad. Sci., Vol. VII, 1877, p. 35. 

 Sharp, Proc. Acad. Nat. Sci. Phila., 1893, p. 116. 



Kostrum slender, strongly ridged on the sides, bent downwards near the 

 base, about one-half as long as the carapace, scarcely exceeding the ante- 

 penultimate basal joint of the antennules; it is armed above with six or 

 seven teeth, the last tooth situated at considerably more than the usual 

 interval from the preceding one and at about the anterior third of the car- 

 apace; below the rostrum is armed with three teeth; a strong spine above 

 and a smaller one below the base of the antenna on the anterior margin. 

 The spine on the outer side of the basal joint of the antennules reaches 

 about two-thirds as far as the tip; last joint of the peduncle nearly as long 

 as the preceding one; flagella subequal and longer than the body. Antennal 

 acicle elongated, exceeding the tip of the antennular peduncle, and wide 

 at the tip, where it is transversely truncated or broadly rounded. External 



1 Proc. Acad. Nat. Sci. Phila., 1879, p. 413. 



2 See Proc. Acad. Nat. Sci. Phila., 1860, p. 26. 



