Directions for preserving Sea Plants. 147 



Thoug-h the above method is in general the best, yet there are va- 

 rious species, and among these the Plocamium coccineum itself, 

 which dry perfectly well by simple exposure to the open air without 

 pressure being- had recourse to at all ; and some can only be preserved 

 in the latter way, being so glutinous that they will adhere as strongly 

 to the drying paper laid over them as to that on which they are 

 spread. Pressure, however, is necessary after they have dried, for the 

 purpose of flattening them.* 



After these general remarks, I will now offer some observations 

 relating to several genera and species, following the order in which 

 they are arranged in the English Flora. 



I believe all the species belonging to the Fucoideae are to be dried 

 in the manner of land plants, after having been previously steeped 

 for some time in fresh water to extract their salt and mucilage. Ci/s- 

 toseira granulata, which I have repeatedly found on the Larne shore, 

 will adhere imperfectly if spread in water, but it is best treated as a 

 land plant, to be afterwards fixed with mucilage. Halidrys siliquosa, 

 Fucus vesiculosus, and F. nodosus require very heavy pressure. 

 The air- vesicles of the first may be in part cut longitudinally to show 

 the internal partitions, and of the two last, to diminish their diameter, 

 but this must be done after they are dried, for if done in the recent 

 state they contract and become disfigured. 



Himanthalia lorea. — Very common on the Antrim coast. It 

 is observed in the English Flora, that the peziza-shaped fronds of this 

 species have been observed " on exposed rocks in the Orkneys swol- 

 len into a large hollow, exactly spherical, smooth black ball, probably 

 in consequence of the heat of the sun rarifying and expanding the 

 air within." I have seen them this summer in a similarly inflated 

 state, not on exposed rocks, but in pools of water where they could 

 never have been uncovered ; they were not black, but of a bright 

 yellow colour, and looked exactly like a parcel of hard-boiled yolks of 

 eggs. I suspect this inflation to be the effect of disease. 



Alaria esculenta. — Common on the Antrim coast. Adheres very 

 well to paper when young, more imperfectly when old. It becomes 



* An indispensable requisite in the drying of marine or fresh water algae is a 

 portion of old rag, neither of a quality too fine or too coarse. When the specimen 

 has been spread, as directed, upon the paper on which it is to remain, a piece of 

 fag sufficient to cover it should be laid over, and then it may be interleaved under 

 the boards for pressure. The rag prevents the necessity of so much care in 

 taking up the moisture as Mr Drummond requires, never adheres to the speci- 

 mens, but when dry, leaves them, while most of the plants themselves stick 

 firmly to the sheets on which they have been spread Eds. 



