156 Directions for preserving Sea Plants. 



in this species are not accidental, but that portions spontaneously se- 

 parate from the frond and drop out. 



Dumontiajiliformis. — Very common. Should be nearly dry before 

 pressure is used. 



Porphyra laciniata — Exceedingly common. This I believe is the 

 only species used in Ireland under the name of Sloke {Laver in 

 England.) It is gathered during the winter months only, the fronds 

 being too tough in the summer. After being properly cleaned, it is 

 stewed with a little butter to prevent its getting a burnt flavour, and 

 is brought to Belfast, where it is sold by measure, usually at the rate 

 of fivepence per quart. Before being brought to table, it is again 

 heated, with an additional quantity of butter, and is usually eaten 

 with vinegar and pepper. I have never heard of any ill eff"ects attri- 

 buted to its use. 



Porphyra vulgaris. — Frequent on the coast, but so excessively 

 abundant at Cairnlough Bay, that it often proved a serious obstruc- 

 tion to my collecting other species, by covering and hiding them from 

 sight. Dr Greville mentions a specimen 31 feet in length, but I 

 saw many specimens of considerably larger dimensions. It is the 

 most difficult plant I know to preserve in perfection, not that there 

 is any difficulty in spreading and going through the other steps of 

 the process, but because, when it has nearly arrived at the last stage 

 of drying, a moment's exposure to the air will cause it to contract 

 so instantaneously, that the edges of the paper are immediately drawn 

 towards each other, and, if attempted to be restored without the 

 whole being first damped, the specimen tears through the middle, 

 and becomes of little value. The edges of the plant adhere strongly 

 to the paper when ^ry, or nearly so, but the centre does not adhere 

 at all, and being as fine as gold-beaters' leaf, though having conside- 

 rable strength, it at once loses the little moisture it possesses, on 

 coming in contact with the air, and contracts with a force remarka- 

 ble, when we consider its extreme thinness. If the paper be thin, 

 its four corners will in a moment be brought almost in contact with 

 each other. I believe the best chance of succeeding is, when we 

 suppose that it is almost dry, to have a flat book (such as a music 

 book) held open, and the pressure being taken off", to remove the 

 specimen along with the drying paper covering it, as quickly as pos- 

 sible, between the leaves of the book, which is to be immediately 

 closed, and not opened till next day, or till we are satisfied that the 

 desiccation is absolutely complete. 



The colour in this species varies very much, — in some specimens 



4 



