From the Proceedings of the California Academy uf Sciences, March 20, 
Description of Seventesn New Species of Cruste 
BY W.N. LOCKINGTON. 
aa 
4 
Platypes, nov. gen. : 
Rostrum simple, post and pre-orbital spines wanting, hinder feet laminate. 
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Platypes edentata. nov. sp. a 
Rostrum laminate, triangular, simple; carapace tuberculate, the tubercles 
not prominent, and each covered with smaller tubercles. 
Form of carapace broad. pyriform; antero-lateral margin not well defined, 
indistinctly lobed; postero-lateral and posterior margins forming a continuous 
curve, without spines or projections. Eyes not projecting, rostrum and an- 
tero-lateral margin forming a continuous line. 
Propodus of first pair smooth, oblong; fixed finger and dactylos closing only 
at the tips, which are somewhat spoon-shaped, manus with an alveolate up- 
per edge. Hinder four pairs broadly laminate. 
Length of largest specimen, a female, 0.44, greatest width, 0.38. 
Three specimens of this small and curious species from Mazatlan, presented 
by Hy. Edwards. Not having seen anything similar, or met with any generic 
description which seems to apply in every respect, I propose to make it the 
type of a new genus. 
Atergatis cristatissimo. ‘ 
Carapace transverse, elliptic, the front and antero-lateral border forming 
the greater portion of an ellipse, the front not projecting beyond the line of 
the ellipse. Antero-lateral margin cristate, the crest divided by short sulci 
into four lobes, of which the 2d is short, the Ist and 3d long, and the 4th 
turns somewhat abruptly inwards, the crest ending half way along the postero- 
lateral border, which is short and only slightly concave. Front slightly 
waved. Areolation distinct upon the central and antero-lateral regions, but 
becoming obsolete posteriorly. ; 
Chelipeds about equal in size, manus with three distinct low beaded ridges 
on the outer side, and a sharp crista above, the latter continued along the 
carpus. Fixed finger short, with a long sharp tooth onits inner face. Dac- 
tylos cristate above, inserted some distance below the upper margin of the 
manus. The fingers are pointed at the ends, and knife-like on their inner 
edges. Hinder limbs cristate, compressed, claws long and sharp. Color 
