HARDWICKE'S SCIENCE-GOSSIP. 



171 



sizes of paper, and these should have each a piece 

 of very fine calico and four pieces of blotting-paper 

 to correspond. The process of mounting one of the 

 filamentous or branching species is as follows : — 

 The specimen being cleaned and placed in the 

 mounting-dish, a piece of paper of suitable size is 

 laid on one of the perforated zinc plates, and both 

 are then slipped quickly under the floating weed. 

 The root or base of the specimen is then pressed 

 down on the paper with a finger of the left hand, 

 while the right hatid is employing [the forceps 

 or porcupine-quill in arranging the plant in as 

 natural a position as possible, ere the zinc plate is 

 gently and gradually raised at the top or bottom, 

 as may be necessary, to insure a perfect display of 

 every portion of the plant ; but if, upon drawing it 

 out of the water, it should present an unsightly ap- 

 pearance from too thick an overlapping of the 

 branches, the whole must be re-immersed, and a 

 little pruning of superfluous portions may be em- 

 ployed with advantage to the specimen and satis- 

 faction to the operator. Care should be taken that 

 the water be drained off the paper as completely as 

 possible before the calico is laid over the plant, and 

 this is accomplished by raising the paper containing 

 the plant as it still lies on the zinc plate, and 

 transferring it to a thin board placed in an inclined 

 position against one of the basins, and with the 

 large camel-hair pencil paint off the water as it 

 runs away from the specimen, and absorb what re- 

 mains, when the paper is laid flat, with the sponge. 

 Delicate species may be left to drain for a few 

 minutes, while the operator is arranging other 

 specimens. When the water is sufficiently drained 

 off, the paper is then laid on the blotter, and the 

 piece of calico is placed upon the plant— a sheet of 

 blotter being laid upon the calico. 



Care should be observed in subjecting plants to 

 pressure, which, in the first instance, should be 

 sufiicieut only to help the absorption of water. The 

 first set of blotting-papers should be changed in 

 half an hour after the whole batch of specimens 

 have been placed in the press, and these must be 

 thoroughly dried before they are used again. After 

 the second or third change of blotters, the plants 

 should remain under strong pressure for two or 

 three days ; but the pieces of calico must not be re- 

 moved until it is pretty certain that the papers and 

 plants are quite dry. 



With the exception of the Euci or common rock- 

 weeds, I never place seaweeds in fresh water : with 

 these, especially Fuciis serratus, F. nodosus, F. 

 vesiculosus, and F. canaliadatus, a few hours' 

 immersion in fresh water is an advantage, as it 

 soaks the salt out of their fronds and renders them 

 more pHable. As all the Euci turn black in drying, 

 and few of them adhere well to paper, I arrange 

 my specimens in single layers between the folds of 

 a clean dry towel, and keep them under pressure 



until they are quite dry ; they may then be put 

 away loosely, or gummed on sheets of paper. 



The foregoing directions for mounting filamentous 

 seaweeds are applicable to all the branching species 

 of Olive, Red, and Green plants ; but in each of the 

 three subdivisions there are a few species which 

 are so gelatinous, — in fact, so soft and spongy, that 

 they require the utmost care during pressure, other- 

 wise they adhere to the calico and break off in 

 fragments as it is drawn away. Such plants must 

 be left to dry in a horizontal position for ah hour or 

 so before the calico and blotters are placed over 

 them, and pressure must be very slight until they 

 have adhered closely to the paper. Among the 

 Chlorosperms, or green plants, there are the various 

 species of Codium, young plants of which only are 

 manageable or indeed desirable. In the Melano- 

 sperms, some species of the genus Mesogloia will 

 require care and patience in mounting, as well as 

 the long string-like plant, known as Chorda filum ; 

 and again, the spreading tuberous mass called 

 Leathsia tuberiformis, portions of which should be 

 cut from the rock, the sand scraped and washed 

 out, then laid on the wet paper, and allowed to 

 shrink for some hours ere calico blotters and pres- 

 sure be applied. These difliculties are much more 

 numerous among the Rhodospcrms, or red sea- 

 weeds, experience only teaching the best method 

 of treatment. I will, however, mention the names 

 of some very troublesome plants, the fronds of 

 which, if subjected to pressure too soon, burst and 

 discharge their carmine contents ; not only pre- 

 senting an unsightly appearance, but destroying the 

 specimen. These are Griffithsla corallina, Dudres- 

 nala coccinea, Naccaria Wiggii, all the Chylocladia, 

 and the rare Gloiosiphoma, as well as the slimy 

 worm-like plant known as \Nemaleon multifidim. 

 In addition to these troubles among the red plants?, 

 there is an opposite difiiculty connected with several 

 Rhodospcrms which must be pointed out ; and that 

 is owing to an absence or scarcity of gelatine in 

 their substance, which is in some of a stout, 

 leathery, or horny nature, and in others is due to a 

 coating of carbonate of lime, which completely en- 

 velops the vegetable structure. Among the former 

 may be mentioned the several species of Phyllo- 

 phora, and several among the genera Gigartina, 

 Chondrus, and Sphserococcus ; and in the latter, all 

 the calcareous Algae, especially the well-known 

 Corallina officinalis and Jania nihens. All these, 

 and several others of a membraneous nature, among 

 the olive as well as the red weeds, must be first 

 mounted in the ordinaiy manner, and when they 

 are tolerably dry and begin to shrink away from 

 the paper, fill the mounting-dish with stale skimmed 

 milk; refloat the plants on their papers in the 

 milk, and indeed go through the same process as 

 before with the sea-water, but be careful to absorb 

 all the milk from off the surface of the plants and 



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