124 



PINNOTHERIDJE. 



" The smallest Pinnotheres I have seen was found by 

 Mr. Hyndman, in a living Cardium exiguum, dredged by 

 us in Strangford Lough in October, 1834. It is a male ; 

 the carapace is under a line in length ; the entire breadth 

 of the crab from the extremities of the outstretched legs is 

 three lines. The cardium is under three lines in length, 

 and barely exceeds that admeasurement in breadth ; so 

 that the crab when in the position just mentioned must 

 have, on both sides, touched the walls of its chosen prison. 

 The Pinnotheres likewise inhabits the Cardium edule. Be- 

 fore me is one of these crabs, of which the carapace is 

 two lines in breadth, obtained by Mr. Hyndman in a full 

 grown C. edule from Strangford Lough ; but from the 

 Sligo coast, where this crab attains an extraordinary large 

 size, a crab with a carapace four lines in breadth, and 

 with outstretched legs seven lines across, was once kindly 

 brought to me by Lord Enniskillen. Mr. R. Ball informs 

 me that on two occasions he obtained a great number of 

 the Pinnotheres, and which were all males, from the 

 Cardium edule taken at Youghal, about nine out of every 

 ten cockles contained a crab. On opening oysters in 

 Tenby, in Wales, he has likewise procured the Pinnotheres. 

 This crab, like the Pagurus, occupies different species of 

 shells according to its size, and at every age generally 

 selects such as with outstretched legs it would fill from 

 side to side." 



It is a point of considerable interest as connected with 

 this species, that it formed one of the subjects of Mr. 

 Vaughan Thompson^ investigations on the transformations 

 of Crustacea, and the description with figures of the Zoea 

 of Pinnotheres as given in a paper by that gentleman in 

 the " Entomological Magazine." * 



* Vol. iii. p. 85. 



