414 Dr. W. C. M'Intosh on Pelonaia corrugata. 



LXL — Notes on Pelonaia corrugata. 

 By W. Carmichael MIntosii, M.D., 1\L.S. 



[Plate XII.] 



A BRIEF description (with drawings) of this animal was read in 

 Section D of the British Association, in August last, under the 

 idea that it was a new molluscoid animal — a mistake which 

 arose from the defective descriptions and figures of Messrs. 

 Forbes and Goodsir in the 'Edinburgh Philosophical Journal' 

 and the 'British MoUusca' of Messrs. Forbes and Hanley. 

 Prof. Huxley, in remarking on the paper, observed that the 

 dependence placed on the descriptions of the above-mentioned 

 authors was too great, and he thought the animal was a Pelo- 

 naia. I am especially indebted, however, to the late Mr. Joshua 

 Alder, who examined the specimen, its description, and the 

 drawings, for much valuable information on the subject, as well 

 as for the accurate determination of the species. 



The specimen (PI. XII. fig. 1) from which the original descrip- 

 tion was drawn up had been about four years in spirit before 

 an examination showed its true nature ; and then, unfortunately, 

 the state of the preparation prevented so precise an examination 

 as might have been desirable. The transmission of another 

 small specimen, however, in a fresh condition has enabled me to 

 correct some doubtful points in the previous description. Both 

 examples were procured at St. Andrews, by relatives, — the larger 

 being cast on shore after a severe storm, the smaller occurring 

 amongst the debris from the deep-sea fishing ofi" the Bay*. 

 Both were injured at the anterior end. The following descrip- 

 tion is thus necessarily fragmentary. 



The test in the larger example measures about If inch in 

 length, possesses a club-shaped outline, and is of a brownish- 

 sandy colour, resembling an elongated Florence fiask with the 

 bottom a little produced and the neck much elongated. In the 

 other specimen the form is more strictly club-shaped, the 

 bulbous end being smaller in proportion to the stalk. The case 

 is rough to the touch, like sand-paper, and bears at the bulbous 

 end a series of minute hairy processes, while the apertures are 

 situated at the extremity of the elongated portion. In structure 

 the external tunic is fibrous, dense, and elastic, and, with the 

 exception of the terminal portion of the smaller end in the 

 larger specimen, loaded with minute and closely adherent sand- 

 paiticles imbedded in a hyaline matrix. Like the more regular 

 and exquisitely fitted, though larger-grained and less elastic 



* A third, much less coated with sand, has just been sent from the 

 same locality. 



