HIPPOTHOA. 293 
2. Hiproruoa pivaricata, Miss Hiliott. (Plate XV. 
fig. 55.) 
Hab. On old shells, especially bivalves, from deep water. 
On oyster-shells, Sidmouth, Mrs. Gatty; on;Pzaua, from the 
island of Coll, D. L.; on different kinds of algze, coast of 
Ayrshire, D. L. 
This is so delicate and slender that it requires good 
eyes to observe it; and when it is old and opake, and on a 
whitish shell, an unpractised eye, even when aided by a 
lens, would scarcely succeed in detecting it. When young 
and fresh it has a crystalline appearance; the cells, which 
are connected by a delicate calcareous thread, are more 
distant from each other than those of H. catenularia. Dr. 
Johnston mentions that there is “a variety of H. divaricata 
in which the cells are contiguous. It is found on seaweeds 
only, so far as my experience goes.” This accords with my 
own experience in so far that I have seen on seaweeds the 
pretty little variety with a very short thread betwixt the 
cells ; yet the very last specimen of H. divaricata which | 
fell in with was on Delesseria simuosa, as transparent almost 
as dew, while the portion of thread which connected the 
sparkling bugles was fully as long as I had ever seen it 
upon shells. | 
