3Y2 CRUSTACEA. 



Oct., 1834, and on a subsequent occasion we obtained several individuals 

 in tbe same locality. It lias been dredged in Belfast Bay by Dr. J. L. 

 Drummond. Dr. Ball once found this s])ecies cast ashore in numbers on 

 the Dublin coast after a great storm ; and in his collection are fine speci- 

 mens from Roundstone, on the western coast. 



Capt. Beechey, R. N., brought up a crab of this species alive in the 

 dredge from a depth of oO fathoms oif the Mull of Galloway. 



On examining otlier specimens in my collection, and finding great 

 diversity as to the isolation and approximation of the tubercles so as to 

 form shields in the difterent individuals, I became certain that the i?. 

 aspera and E. scutelhita are but one species, the latter being a state of the 

 former with the tubercles drawn together so as to form shield-like 

 patterns. The shields in all the specimens examined, except the first- 

 mentioned, show that they are formed by the junction of the tubercles : 

 in it however no trace of the separate tubercles is visible, but instead, the 

 five on either side the central one on the cardiac region are all fused 

 together. Those forming the smaller shield anterior to it are likewise 

 fused together so as to leave no trace of the number of tubercles 

 forming it. 



Genus Xantho. 

 X.Jlorida, Leach, 



Seems to be a local species. It is recorded as Irish in Mr. J. V. 

 Thompson's catalogue. In the Ordnance collection are specimens from 

 three localities on tlie Antrim coast — Carnlough, Lame, and Carrick- 

 fergus ; and in Dr. Ball's cabinet there is an example from Dublin Bay. 

 In July, 1840, this species was found commonly by Professor Forbes and 

 myself under stones between tide-marks at Lahinch, County Clare : — the 

 entire claws of these specimens (all under half adult size) are of a pale- 

 brown colour, but very different in shade from any part of the body of the 

 animal : in Leach's Malacostraca the claws are described and figured as 

 black, but a variety stated to be rare is said to have " the tops of the 

 claws of the same colour with the other parts of the animal." 



Abundant under stones on the beach, Tory Island, Mr. Hyndman. 



X. rivnlosa, Risso. 



A fine example of a crab so named, and which is an addition to the 

 British Fauna, is in the Ordnance collection — it was taken at Portrush, 

 County of Antrim, in July, 1839. Col. Portlock informs me that having 

 been at once identified as the X. rivulosa, more specimens were assidu- 

 ously sought for in the locality, but in vain. I fully agree with him in 

 considering it the A', rirnlosa as described by M. Edwards. It seems to 

 me a well-marked species. It is said to inhabit the Mediterranean and 

 the western coast of France. 



Ge7ius Cancer, 

 C. Faf/urits, Leach. 



This, the common edible crab, is taken on all quarters of the Irish 

 coast, and is held in good estimation for the table. It is the only species 

 brought on sale to Belfast market. In January, 1836, a specimen weigh- 

 ing OHbs. was taken in Strangford Lough, and in Aug., 1841, one of 

 9 lbs. was obtained in Belfast Bay : these were of extraordinary magni- 

 tude for the North of Ireland to produce, although not larger than what 

 are commonly to be seen in the London market. M. Edwards mentions this 



