322 INVERTEBRATA OF MASSACHUSETTS. 



Cancer Maenas, LIN.; Syst. JVaf. xii. 1043. PENNANT ; Brit. Zool., iv. pi. 2, f. 5. 



HERBST; Cancr., pi. 7, f. 46. LATR. ; Encyc., pi. 273, f. 1. LAM. ; An. sans 



Vert., v. 494. Bosc ; Crwsf . , i. 202. 

 Carcinus Mamas, LEACH ; Malac. Podoph. Brit., pi. 5. MILNE-DW. ; Hist, des 



Crusty i. 434. 

 Cancer granulatus, SAY ; Journ. Acad. Nat. Sc. } i. 61. 



This crab is characterized by the five acute teeth on each side, 

 and its three-lobed front. Its surface is not raised into promi- 

 nences, but granulated merely. It is of a sea-green color. The 

 wrist has a single spine inside. Length an inch and a half or two 

 inches ; breadth a little more. 



Sent by Dr. Yale from Martha's Vineyard. 



There can be no doubt that our crab is identical with the Euro- 

 pean species, as an interchange of specimens has shown. It is 

 employed for food in Europe, but not in this country. 



GENUS CANCER, LIN. 



C. IRRORA'TUS. Carapax with nine crenate teeth on each side ; 

 front three toothed ; hands with four or five elevated lines on the 

 external side. 



C. irroratus, SAY ; Journ. Acad. Nat. Sc., i. 59, (in part.) BELL ; Trans. Zool. 

 Soc. Land., i. 340, pi. 46. 



Carapax transversely oblong-oval, slightly angular at the sides ; 

 regions slightly marked ; surface covered with minute, raised gran- 

 ulations. Margin, each side, slightly divided into nine quadrangu- 

 lar lobes, the lines of division extending far inwards, and the pos- 

 terior one having an indentation at base so as to form almost a 

 tenth tooth ; each lobe is minutely denticulated, one or two of the 

 denticles being larger than the rest. Middle tooth of the front 

 longer than the others, and depressed. Orbits circular, with a 

 tooth over the inner angle and two fissures over the centre, and 

 beneath. Abdomen and sternum slightly fringed with hair. Limbs 

 short, fringed beneath, the nails tipped with black. Carpus 

 marked with granulated lines, and having a sharp spine at its inner 

 angle. Hands rather large, smooth on the inner face, with den- 

 ticulated lines above, and having four or five granulated lines on 

 the outside, two of which are continued upon the finger, which is 

 somewhat deflexed, and, with the thumb, is slaty-black at tip. 



