172 Prof. F. M‘Coy on the Classification of 
developed abdomen, caudal fins, remarkably large false feet, and 
all the characters of the Macrura, being in fact clearly referrible 
to the genus Mecochirus of Germar, so abundant in the upper 
oolitic schists of Bavaria, though not hitherto recognised in Bri- 
tam. The five internal processes mentioned on each side are 
merely the indications of the apodemata or internal partitions 
between the gills, and present no peculiarities. As the specific 
name longimanus would be peculiarly inappropriate when this in- 
teresting little crustacean is placed in its true genus (nearly all 
the species of which have longer hands), it might provisionally 
bear the name of Mecochirus Pearcei. 
(Macrura.) 
In this group we find several fossil crustacea referred to recent 
genera in British works, without, I believe, just reason :—thus in 
Morris’s Catalogue we find Palinurus Seurti quoted from Leeds, 
Yorkshire ;—if this muschelkalk fossil is found there, it should 
be placed in the Triassic genus Pemphizx, formed many years ago 
for it by Von Meyer, it having no relation to Palinurus. The 
recent generic name Astacus has also been much used for fossils 
of various ages, but I have not yet seen or heard of the real oc- 
currence of that genus in the fossil state ; most of the species will 
be noticed below under their respective genera. 
Eryon Barrovensis (M‘Coy). 
Sp. Char. Carapace subovate, about one-eighth broader than long 
near the truncated posterior margin ; lateral margins set with 
short tooth-like spines, two narrow incisions on each side, the 
hind pair a little in front of the middle, inclosing between 
them on each side a short rotundato-quadrate lobe ; front har- 
rowed, concavo-truncate, with the lateral angles slightly pro- 
duced outwards ; each of the inner pair of antenne having their 
two sete deeply divided, the outer one of each slightly longest, 
scale of the external antenne large, the sete scarcely thicker 
than those of the inner pair ; abdomen exceeding the length of 
the carapace by only one-third the length of the outer tail- 
flaps, which latter are very broad and subquadrate at the end 
(resembling those of the Eryon Hartmanni) ; each of the seg- 
ments except the first bears a large, oblong tubercle m the 
middle ; first pair of legs robust, short, hand and carpus to- 
gether nearly one-fourth less than the length of the middle of 
the carapace ; fingers very slender, both pointed, of equal 
length, incurved at the tip, the moveable one most abruptly. 
Surface minutely granulated, with larger granules on the me- 
sial ridge of the carapace. Length of carapace 2 inches, width 
2 inches 2 lines ; length of abdomen (to end of outer pair of 
