LEPRALIA. 305 



breadth. When young, they are pellucid and smooth. 

 The capsules are projected in front of the constricted aper- 

 ture, and are perforated on the top. The cells are sur- 

 rounded with a series of apertures. 



3. LEPRALIA ASSIMILIS, A. H. Hassatt. 

 Hab. Dublin Bay, Hassall. 



Though this resembles L. tenuis, Mr. Hassall thinks it 

 is distinct. Dr. Johnston, judging from Mr. HassalFs de- 

 scription, can see no characteristic difference betwixt them. 

 Four specimens of it were got by Mr. Hassall on Pecten 

 maximus. 



4. LEPEALIA HASSALLII, A. H. Hassall. 



Hab. On shells, rare. Dublin Bay? A. H. Hassall; on 

 Patella ccerulea, coast of Ayrshire, D. L. 



We remember finding this, many years ago, adorning the 

 summit of a P. carulea, cast out on the shore at Saltcoats. 

 It was new to me, and I sent it to Dr. Johnston, who was 

 then preparing for the press the first edition of his ' History/ 

 He received it afterwards from Mr. Hassall. It is com- 

 posed of large cells, horizontal and cylindrical. The aper- 

 ture is wide, with a small sinus above and a large knob on each 

 side. The capsule, situated below the aperture, "mimics 

 the swollen lobe of the flower of a calceolaria/' (Johnxton.} 



X 



