ADDITIONS TO "BRITISH CONCHOLOGY." 



By J. T. MARSHALL. 



Part VII. {continued from p. 128). 



Adula (Myrina) simpsoni Marsh. — In the Journal for October 

 last, p. 126, under this name, I omitted to add the following additional 

 particulars of this interesting species : — Soon after its original dis- 

 covery, attached to the skull of a whale brought into the Aberdeen 

 fish market by a trawler, some further specimens were discovered in 

 a piece of pitch pine, which had been bored by Xylophaga and Teredo, 

 and in the deserted tubes of which were about two dozen of these 

 Adula, attached by a byssus. Several were alive, and were placed 

 under examination. " They were quite at home in a watch-glass, and 

 travelled by first protruding the foot, and then contracting it, so as to 

 draw the shell along," while under the microscope "the action of the 

 current through the tubes could be seen through the valves of the 

 shell" (Simpson in. liiL). A specimen sent me in spirit yielded the 

 following results, which demonstrates that the animal is not far 

 removed from Modiolaria : — Body dirty white, viscera light brown, 

 mantle free, plain ; incurrent tube formed by two flaps of the mantle; 

 excurrent tube short, thick, and conical ; foot white, tongue-shaped, 

 with a conspicuous groove down the centre for the byssus. The 

 habitat of these specimens in perforated wood brings it into com- 

 plete harmony with the discovery of A. argenteus Jeff., from frigid 

 water in the Shetland-Faroe Channel, which also occurred in per- 

 forated wood. 



Soon afterwards, a few examples were found on a whale's skull 

 trawled about 25 miles N.W. of Fair Isle, and a dozen more were 

 trawled off the East Shetlands in 80 fathoms on the broken jaw of a 

 whale. These latter were aged specimens, equal in length and breadth 

 to the largest previous examples, but more than twice the girth, and 

 darker in colour. 



As bearing on the peculiar affinity of tlie Adula for whales' skulls 

 and bones, the Faroe Islands ought to produce a rich harvest of these 

 molluscs, seeing that there is a considerable whale fishery carried on 

 by the Faroese, and the Faroe seas are strewn with the skulls and 

 bones of whales, which are frequently brought to land. The Faroese 

 Avhales are chiefly of the bottle-nose and Grindeval species, which are 

 captured for the sake of the blubber, while the ribs are frequently 

 used for the construction of wails and fences. 



Galeomma turtoni Eds. Zool. Journ. — Alderney, a valve m 

 shellsand (Marquand)! 



