324 HISTORY OF BRITISH ZOOPHYTES. 



pretty easily distinguished, though it assumes some variety 

 of forms. The cells are ovato-globose, frosted ; the aperture 

 sub-circular, with from three to seven spines, those in the 

 middle being long, and those at the sides short. There are 

 no spines on the upper lip, but there is a knob above it. 

 The L. insignis of Hassall, besides the spines on the upper 

 lip, has a single spine arising from the side. I remember 

 that he was pleased when I sent him specimens of it from 

 our Ayrshire coast, where it is pretty common. It is smaller 

 and neater, but Dr. Johnston thinks it is only a variety of 

 the normal state. 



33. LEPRALIA SPINIFERA, A. H. Hassall. 



Hab. Rather abundant on stones and shells, in Dublin 

 Bay, A. H. Hassall. 



This differs from L. ciliata scarcely in anything except 

 that it has a sinus in the upper lip. 



34. LEPRALIA TRISPINOSA, Dr. Johnston. 



Hab. On shells, Berwick Bay, rare, Dr. Johnston ; coast 

 of Cornwall, Mr. Peach ; near Aberdeen, on roots of Lami- 

 naria digitala, J. Macgillivray. 



Crust often silvery white, with minute yellow dots ; cells 

 rough ; aperture a little cleft above, having three stout long 

 spines on the under lip. 



