30 NATURAL HISTORY OF 



shells of roraminifera, principally of the genus Amphiste- 

 gina, a type characteristic of tropical and sub -tropical 

 regions, but also containing examples of Nodosarim of the 

 dentaline structure, and of numerous small portions of corals 

 of various species. A few small shells of Molluscs were also 

 present, and among these I recognised an Oliva, a Lima, and 

 a diminutive Pecten. In addition to these, several fragments 

 of a Serpula, and a spine and portion of the dental apparatus 

 of a small Echinus, occurred. Of the shell of Amphistegina, 

 Dr. Carpenter has given an elaborate account in his learned 

 and valuable Introduction to the Foraminifera,^ observing that 

 " it closely corresponds in external form with that of JVum- 

 mulina," but that "it is only for some of the smaller 

 ]N'ummulines that it could be mistaken, since its diameter 

 seldom exceeds the l-8th of an inch." As regards its 

 geographical distribution, he states that it has been found "in 

 various parts of the Indian Ocean, the great Polynesian area, 

 and the West Indian Seas ; " that the farthest limits to which 

 it is known to extend northwards are the Eed Sea and the 

 neighbourhood of the Canary Islands, while southwards, it has 

 not been traced further than ISTew Zealand ; and that it occurs 

 in greatest size and abundance in depths of from 15 to 50 

 fathoms, but that small specimens have been brought up 

 from abyssal soundings in the Eed Sea. The species 

 obtained on the Jaseur Bank, which varied in size from 

 a twentieth to a tenth of an inch, is very convex on the 

 upper, and flattened or concave on the lower surface, and 

 bears a close resemblance to Amphistegina mamillata of 

 D'Orbigny, as figured in the Introduction to the Foramini- 

 fera. As regards Nodosaria, on the other hand, Dr. Car- 

 penter remarks, that, under some one or other of its protean 



* Page 242. 



