1898—1902. No. 18. CRUSTACEA. 31 
carrying at some distance from the tip a strong deflexed spiniform 
appendage accompanied by another much thinner appendage. Last pair 
of legs very small, distal joint quite short, with only 5 sete, 2 of them 
attached to the inner edge; inner expansion of proximal joint tipped 
with 2 unequal sete. 
Length of adult female 0.77 mm. 
Remarks. — The present form is easily distinguishable from 
the preceding species and also different from any other species known 
to me. In the shape of the rostrum and the ist pair of legs it some- 
what resembles A. imus (Brapy); but the body is far less slender, and 
the structure of the last pair of legs is also very different. 
Occurrence. — Several specimens of this form occurred in a 
bottle of specimens taken on July 12, 1900, in the bay at Land’s End. 
109. Amphiascus brevis, G. O. Sars, n. sp. 
(Pl. VIII, figs. 11-15). 
Specific Characters. — Female. Body unusually short and 
stout, with the anterior division slightly dilated in the middle and some- 
what narrowed both in front and behind. Rostrum of moderate size 
and obtusely pointed at the tip. Urosome considerably shorter than 
the anterior division, with the last segment about the length of the pre- 
ceding one. Caudal rami broader than they are long, inner medial 
seta conspicuously dilated at the base and not quite twice as long as 
the urosome. Anterior antenne rather slender, 8-articulate, with the 
Ath joint longer than the 3rd, terminal part about half the length of the 
proximal one. 1st pair of legs with the outer ramus exceeding half 
the length of the inner, and having the last joint about as long as the 
middle one, its armature as in the 2 preceding species; inner ramus 
with the 1st joint long and slender, seta of inner edge comparatively 
short, outer 2 joints less unequal than in A. polaris, the last one being 
only slightly longer than the other, and armed at the tip with a mode- 
rately slender, almost straight claw and a long seta accompanied by a 
small bristle. Natatory legs normal. Last pair of legs comparatively 
smaller than in the preceding species, distal joint narrow oval in form 
and somewhat exserted at the end, marginal sete 7 in number, 2 of 
them being attached to the inner edge; inner expansion of proximal 
joint extending to about the middle of the distal joint and carrying 
5 sete. Ovisacs about as in A. polaris. 
Length of adult female 0.52 mm. 
