ON CEISTISPIRA VENERIS NOV. SrEC. 



513 



I take this opportunity of thanking the Rev. A. H. Cooke 

 for very kindly ideuti tying these Lamellibranchs for me. 



A good deal has already been written about the function of 

 the crystalline style of the Lamellibranchiata. It has been 

 suggested that it is a body of a secretory or excretory nature, 

 that it is a reserve supply of food material, and that it is a 

 mechanical device for catching and conglomerating food 

 particles. Mitra ^ has shown that it contains a proteid sub- 

 stance — which he showed to be a globulin — and that an 

 amylolytic ferment is present in it. He therefore regards it 

 as a body which is primarily connected with the digestion of 



1 Mitra. " The Crystalline Style of Lamellibranchia," ' Quart. Journ. 

 Micr. Sci.; vol. 44, 1901. 



