some British Fossil Crustacea. 165 
_ This rare species is distinguished from the common Z. nodosa 
and Z. bispinosa by its more uniform convexity and by the orbi- 
cular form produced by the length so nearly equaling the width, 
as well as the single, angular, pointed spine on each side. The 
different projections on the posterior half of the carapace are 
much less strongly marked than in the other species, though 
having the same form and position. 
Rare in the London clay of Sheppey. 
(Col. University of Cambridge.) 
Of this genus (Zanthopsis) authors describe from the London 
clay at Sheppey the Cancer Leachii (Desm.), which from the im- 
perfection of the specimen described originally (even the mar- 
gins of the carapace being absent), I do not think it is possible 
to recognise with any certainty. Also belonging to it and from 
the same locality is the Brachyurites hispidiformis of Schlotheim 
(Nachtr. z. Petrefactenk. t. 1. f. 3), which for a wonder has 
escaped insertion in my friend Mr. Morris’s elaborate ‘ Cata- 
logue’; it has the exact form and strong nodulation of the Z. no- 
dosa, but having the two posterior pair of spines even more pro- 
duced and slender than in the Z. bispinosa. 
Podopilumnus (M‘Coy), n. g. 
Gen. Char. Carapace having the front and antero-lateral margins 
forming a_semielliptical 
curve, antero-lateral mar- 
gins not compressed, tu- 
mid, obtusely rounded, 
with aboutthree small spi- 
nose tubercles ; front nar- 
row, slightly projecting, 
deeply four-lobed (inclu- 
ding the inner angles of 
the orbits), with a shal- 
low furrow extending a 
short way on the back 
from the middle notch ; 
orbits large, oval, lower 
margins denticulated, a 
small fissure in the under ——— 
margin at the outer angle Diagram of the genus Podopilumnus. 
(and a doubtful trace of @ Carapace, thighs and chele; 6, abdo- 
one in the upper margin) : men of sie two last dotted joints 
put in from their impressions on the 
posterior lateral margin breast-piece ; ¢, profile of carapace 
straight, longer than the showing the abrupt downward curve of 
anterior, converging to- _ the front. 
wards the truncated base; posterior half of the carapace flat- 
