The Rev. W. Hincks on Balanus chelytrypetes. 333 



XL. — Description of a new Species of Balanus, from the 

 Cabinet of Samuel Wright, Esq., of Cork. By the Rev. 

 William Hincks, F.L.S. 



Mr. Wright, who is a zealous collector in several depart- 

 ments of Natural History, and is well known from his valu- 

 able contributions to the fossil conchology of the interesting 

 district in which he resides, transmitted the species now to be 

 noticed to the present writer to be examined and compared 

 with the specimens in the British Museum, and on finding 

 that it is undescribed, requested that some account of it might 

 be communicated to the public. 



This animal may perhaps belong to the genus Balanus, 

 though Mr. Gray is of opinion that it must form the type of 

 a new genus, and it is a question which may be left for future 

 decision. 



It is attached to the common turtle. The shell consists of 

 six valves, slightly cohering, unequal in size, the smallest and 

 largest being opposed to each other, each valve externally 

 marked by two or three strong ridges meeting towards the 

 apex, sometimes further branched below, which penetrate the 

 bone of the turtle like the fangs of teeth, and appear to enter 

 the fat underneath. They at length almost, perhaps altogether, 

 cut out the portion of bone on which the Balanus stands, so 

 that the removal of the shell would leave a roundish hole. 

 The opercular valves are lost in Mr. Wright's specimens, 

 which were injured in cutting up the turtle. The diameter of 

 the base in the largest specimen is 1*8 inch. The Balanus 

 being firmly attached to the bony covering of the turtle, which 

 it penetrates in the manner described, protrudes through the 

 horny exterior shell ; but a young specimen apparently of the 

 same species is fixed to the internal surface of the horny shell, 

 not having yet either attached itself to the bone or forced its 

 way through the outer covering. 



A specimen in the British Museum which seems to be of 

 the same species, though the fangs are less developed, had its 

 peculiarity of appearance attributed to accidental injury, until 

 a comparison with Mr. Wright's specimen showed its real 

 nature. 



