70 
It was found in a crab pot in June 1837, and though of 
small size, appearing to the fisherman to be of rare occurrence? 
it was reserved for my inspection. It was scarcely the fourth 
of an inch across the carapace, the form and colour resembling 
those of the common Edible Crab, but the area was covered 
with small warty protuberances. On the margin between the 
ocular cavities were five segments, the central most project- 
ing ; on the lateral margin nine crenations, each, as also those 
between the eyes, distinctly but finely notched. Antennae 
small, fine, simple, and with the palpi resembling those of the 
common crab. Hand claws and walking legs short, the two 
outer segments of the former with a serrated crest; the finger 
also notched at its root. Walking legs with short bristles. 
It may be that this is not uncommon, as its small size may 
easily cause it to be overloked ; but uncertain whether it has 
been described before, I have provisionally named it: 
C. Incisocrenatus. Couch’s M.S. and fig. 
GENUS P1LUMNUS: second portion of the outer antennse 
placed in the inner cantlius of the orbit, and extending be- 
yond the front. Carapace rounded over the summit and 
without lines. 
FURRY PILUMNUS. P. Hirtelhis. M. Edwards’ Crust., 
vol. 1, p. 417. Leach’s Malac., pi. 12. Pennant, pi. 6, fig. 
11. Common under stones at low water mark. 
GENUS PIRIMELA : carapace rounded in front, and about 
as wide as long, strongly embossed, and toothed at the 
sides; the third articulation of the inner foot jaws giving 
insertion to the next on its internal edge. 
DENTICULATED PIRIMELA. P. Denticulata. M. Ed- 
wards’ Crust., vol. 1, p. 424. Leach’s Malac., pi. 3. This 
is the only known species of the Genus, and it is not 
common. 
PORTUNIANS, SWIMMING CRABS. 
GENUS CARCINUS: terminal articulation of the hindmost 
legs lancet shaped and straight. Front of the carapace 
advanced, broader than long. 
COMMON HARBOUR CRAB. Carcinus Mcenas. M. Ed- 
wards’ Crust., vol. 1, p. 434. Leach’s Malac., pi. 5. Pen- 
nant, pi. 2, fig. 5. 
One of the commonest Crabs of our shores, where it hides 
under stones or in the beach, but never goes far from land. 
It. is an hardy species, easily kept in confinement for the sake 
of observation, and has even survived the being kept in fresh 
water. 
GENUS PLATYONICIIUS : hinder legs with a wide and 
oval terminal articulation ; corresponding part of the other 
legs straight and unfit for swimming. 
