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THE ZOOLOGIST. 



though widely spread, is comparatively rare. A single specimen 

 was brought in at Portwrinkle in May, 1902. It has been occa- 

 sionally obtained near Mevagissey, has been twice dredged in 

 Carrick Eoads, Falmouth, and has occurred in trawl-refuse from 

 outside the Bay. In July, 1906, a solitary example was obtained 

 immediately south of the Gear Eock, Mount's Bay, in 5 fathoms. 

 It has not been identified from Scilly or from the north coast. 

 There is apparently no recent record of the occurrence of Blastus 

 tetraodon (Pennant) in Cornish waters. Cocks reported it as rare 

 in Carrick Roads and in trawl-refuse. Pisa biaculeata (Mont.) is 

 irregularly distributed but nowhere common from shallow water 

 downwards. It is frequently taken in Crab-pots at Polperro, 

 Mevagissey, Gorran and Scilly, and occasionally appears in 

 trawl-refuse outside Falmouth and Mount's Bay. Single speci- 

 mens have been taken at Porthoustock and at Zennor, and two 

 at Mousehole. The Corwich Crab, Mamaia (Maia) squinado 

 (Herbst), is very common and in places abundant in inshore 

 waters all round the coast from April or May till September, 

 when it gradually diminishes in numbers. In most localities it 

 vanishes into deep water by the end of November. During the 

 summer months it is usually very troublesome among Crab-pots, 

 and often greatly interferes with trawling operations in shallow 

 down to moderately deep waters. In the last week of May, 1907, 

 the trawl brought up a number of very large specimens in 

 40 fathoms some miles E.S.E. of the Lizard. Occasionally very 

 fine, highly decorated examples are brought in by trawlers from 

 deep water at the mouth of the Bristol Channel, and from about 

 50 fathoms fifteen miles W.N.W. of Tresco. The largest speci- 

 men the writer has handled from Cornish waters was taken in 

 the pot of a French crabber at the Seven Stones. Its carapace 

 measured nine inches in length and just over seven in breadth. 

 In the month of August, 1905, this Crab was singularly abundant 

 at Millook, near Bude. At Scilly it is at times uncomfortably 

 common throughout the summer in moderately deep water. It 

 is found in berry in April, May, June and August. Inachus 

 dorsettensis (Pennant) is irregularly distributed, but on the whole 

 common from shallow water down to 45 fathoms on clean sand 

 and gravel bottom and on " scuddy " ground along the south 

 coast, is of frequent occurrence at low water and occasionally 



