166 Prof. F. M‘Coy on the Classification of 
tened, anterior half abruptly sloped downwards towards the 
front ; whole surface even and nearly smooth, the only regions 
defined are the cardiac and intestinal, which are marked by 
shallow furrows (P. Peruvianus) ; sides minutely granular ; 
abdomen of the female broad oval (apparently of seven joints) ; 
four hinder pair of feet subequal, shghtly compressed, very 
long, the thigh (or third joint) alone equaling the posterior 
lateral margin of the carapace in length; chele short and 
strong. 
So far as the imperfection of the specimen allows of examina- 
tion, the most striking difference between the present genus and 
the recent Pilumnus consists in the great proportional length of 
the legs, which are rather longer and more slender than those of 
the Galene Natalensis of Krauss (see his Siidafrikanischen Crust. 
t.1. f.4), to which it bears some resemblance; the tail of the female 
is more ample, and the tumid rounding of the antero-lateral mar- 
gins and their small uncompressed spines contrast strongly with 
the similar parts in the recent genus. The only two known spe- 
cies are the following, and the so-called Portunus Peruvianus 
figured by D’Orbigny in the geological volume of his great ‘ Voy- 
age dans Amérique méridionale’ (t. 6. f. 17), of uncertain ori- 
gin, but which he suspected to have come from the cretaceous 
beds of the Cordillera ; a view I think confirmed by the geological 
place of the second species of the genus, which therefore at pre- 
sent would seem confined to the cretaceous system, and is I be- 
heve the oldest of the genuine Brachyura known. 
Podopilumnus Fittoni (M‘Coy). 
As this is the only accessible species of the genus, it will be 
sufficient, in addition to the above characters, to add the following 
particulars :—Length of carapace 1 inch 5 lines, width 1 inch 
9 lines, general surface smvoth, sides minutely granular ; hands 
about 7 lines wide and 1 inch 1 Iine long, the obtusely keeled 
upper edge with five or six obtuse tubercles, the outer surface 
minutely shagreened and bearing three or four irregular longi- 
tudinal rows of small tubercles ; fingers short, curved, rounded 
on the outer edge, and with three or four blunt teeth on the inner 
edge ; dail 61 lines broad, only the five proximal joints preserved, 
but the fifth being about the same length as the fourth, it 
is probable the remaining two were distinct, it being generally 
at that part of the tail that anchylosis occurs in those genera 
which have less than the normal number of abdominal or tail 
segments. 
Greensand of Lyme Regis. 
(Col. University of Cambridge.) 
