Note 113 — LETTERS TO MERRETT.

In Sir Thomas Browne's time the Hydrozoa were not distinguished from the Corallines, and both were regarded as vegetable growths. It is almost impossible to determine from his vague descriptions even to which section those mentioned belong, but although our exposed coast-line is not favourable to such growths, there are a few common species of Hydroid Zoophytes which abound here, and to these, fortunately, Browne's specimens appear to belong. What he calls the "Sea-perriwig" is doubtless Sertularia operculata, Lin., sometimes known as "Sea-hair," a very common and widely dispersed species.