some British Fossil Crustacea. 177 
about three large sharp teeth each ; rostrum large, deeply chan- 
neled in the middle, sides rising to very prominent keels mi- 
nutely serrated towards the end, one elongate tubercle on each 
side of its base; nuchal furrow strong, ends curved forwards, 
but only extending about halfway from the middle of the back 
to the side margin ; beneath and in froxt of each of its ends a 
very deeply marked -shaped sulcus ; surface very closely and 
minutely granulated, punctured on the cardiac and intestinal 
region ; ends of the abdominal segments broadly rgunded with 
a small mucronate point directed backwards; the last two 
joints with rough transverse scale-like sculpturing, the others 
so finely granulated as to appear nearly smooth. 
This species is remarkable for the size and prominence of its 
sharply angulated cheek-ridges ; the surface, particularly of the 
abdomen, is more nearly smooth than in the other species which 
I have seen. 
Common in the Speeton clay of Speeton, Yorkshire. 
(Col. University of Cambridge.) 
Hoploparia gammaroides (M‘Coy). 
Sp. Char. Carapace averaging from the erbit to the posterior 
side-margin 23 inches, depth 13 inch, minutely punctured on 
the middle of the back, coarsely squamoso-punctate on the 
gastric region, granulated on the sides, most strongly near the 
front lateral margins ; nuchal furrow strong, but only reaching 
halfway down the sides, its middle portion equally distant 
from the edge of the orbit and posterior margin of the cara- 
pace, or slightly nearer the former; A-shaped cheek-furrow 
deep; rostrum strongly bicarinate, with a ridge-lke tubercle 
about two lines long on each side of its base, and one small 
tubercle at an equal distance below the first pair at the edge 
of the orbit ; from a little behind the level of the orbit the 
cheek is elevated into a streng keel with about three large 
spinose tubercles, cheeks prolonged as a_semicylindrical 
sheath to the outer antenne half the length of the rostrum : 
abdominal segments very flat and smooth, the articular ante- 
rior portion scarcely convex, and the sulcus dividing it from 
the posterior portion not very strong, first segment closely 
punctured like the middle of the thorax, the dorsal portion of 
the others with the puncta slight and distant, flaps of the tail 
coarsely squamoso-punctate ; chele very large, with a rude 
seale-like sculpturing of the surface, broad one having the 
hand as wide (14 inch) as from the carpus to the base of the 
moveable finger, four large, short spines on the inner margin, 
moveable finger longer than from its base to the carpus; car- 
pus with several thick short spies; smaller hand as long as 
Ann. & Mag. N. Hist. Ser. 2. Vol. iv. 12 
