LEPRALIA. 303 
cies and another, and owing also to the different aspects 
which, from age and various other circumstances, the same 
species present. When Professor Fleming’s ‘ British Ani- 
mals’ was published, in 1828, only five species were de- 
scribed. By the time Dr. Johnston’s first edition of his 
work on British Zoophytes appeared, more than double 
this number were described and illustrated; and when the 
second edition of his ‘ History’ was published, it contained 
the description of thirty-seven species; and the author 
states that, extensive as the list was, he had specimens 
which he could not confidently refer to any of the species 
described. We know that several distinguished Naturalists 
are at present at work with these little beauties, exercising 
upon them all their powers of discrimination; and we are 
glad to learn that some of them intend to favour the public 
with the result of their investigations. We should be afraid 
to attempt describing the whole of these pretty little puz- 
zlers; and though we had the boldness, the limits of our 
work would compel us to rest satisfied, in many cases, with 
doing little more than inserting the name. 
* Walt of the cells smooth. 
1. LEPRALIA HYALINA. 
Hab. Parasitical on shells, stones, and alge. Shores of 
