344 WISTORY OF BRITISH ZOOPHYTES. 
I insert also in this place, by the same kind permission, 
Mr. Busk’s account of this zoophyte, new to our British 
Fauna. 
“In stating the form of the cells in this genus, it is more 
convenient usually to refer to the back view of them, as I 
have done in this case. 
“In habit this species bears so close a resemblance to — 
S. scruposa that to the naked eye there is very little differ- 
ence between them. ‘The branches are a little broader, and 
perhaps more regularly and more closely disposed. The cells 
are wider in proportion to their length than in that species, 
and their sides, especially the upper one, more square 
and straight. ‘The principal difference in the form of the 
cell consists in the existence in S. scrupea of a rather deep 
depression or sinus on the back of the cell, and towards 
the outer margin, in which sinus is lodged the widraculum*. 
This organ is placed considerably more behind the cell than 
it is in S. seruposa, and differs somewhat in shape from the 
same organ in that species. It is wider, flatter, and, as it 
were, of a spatulate form. ‘The avicularium occupies the 
same position, or nearly so, as in that species, or perhaps is 
* Mr. Busk employs this term to signify the organ furnished with a 
moveable or vibratile seta, as distinguished from the prehensile avicularia. 
