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, fioe, 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 PJLUMNUS: second portion of the outer antenna? 

 placed in the inner canthus of the orbit, and extending be- 

 yond the front. Carapace rounded over the summit and 

 without lines. 

 FURRY PILUMNUS. P. Hirtellus. 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 PLATYONICHUS: hinder legs with a wide and 

 oval terminal articulation ; corresponding part of the other 

 legs straight and unfit for swimming. 



