1887.] NEW-YORK MICROSCOPICAL SOCIETY. 73 



as follows : by using sea-salt (which can be bought for a trifle at 

 any first-class druggists) and distilled or rain water, a. good sub- 

 stitute for sea-water is obtained ; into this I immerse the rough 

 dried specimens of algse, and in an hour or two they have re- 

 sumed their natural shape. Now picking out and clipping off 

 such pieces as are best adapted for mounting, I transfer them 

 to a bowl of distilled water and wash them clean, and from thence 

 transfer them to a small saucer, containing a saturated solution 

 of salicylic acid. The shallow cell into which they now go is 

 built up of shellac cement made by dissolving bleached shellac 

 in cologne spirits. Cells made of this substance are ready for 

 use twelve hours after being laid on to the slide. I pick up the 

 specimen with forceps, put it on the slide, and fill up the cell 

 with the salicylic acid. I now breathe on the covering glass and 

 put it in its place, and by the use of blotting paper absorb the 

 superfluous fluid. A thin coating of gold size completes the 

 work for the time being ; in a day or two I lay on more gold 

 size, and afterwards white zinc cement or brunswick black — the 

 finish, of course, being a mere matter of fancy. 



" In mounting a piece of algae having Isthmia parasitic on it, it 

 is almost impossible to fill these diatoms if balsam is used, 

 whereas by the use of salicylic acid every valve will be filled. 

 In some cases the medium I have used has robbed the alga of 

 its color, but this occurs but rarely. 



" I have now before me a slide of Ptilota hypnoides in full fruit, 

 the beauty of which could never be brought out except by first 

 immersing the specimen in the sea water I have referred to. 

 For the study of algae, direct light should be used, but using 

 dark field illumination is the best way of making it a genuine 

 'Oh my !' slide." — H. F. Atwood, in I'he American Journal of 

 Microscopy, Vol. II. (1877), p. 154. 



The "Curl" of Peach Leaves, and the Fungus, Exoas- 

 cus Deformans. — The Botanical Gazette, Vol. XII., No. 9 (Sep., 

 1887), p. 216, publishes from "Contributions from the Botanical 

 Laboratory of the University of Michigan, 1887," a most admira- 

 ble article, by Etta L. Knowles, on "the disease of peach leaves, 

 known as 'the curl,'" caused by the fungus '''' Exoascus de- 

 formans.'' The article is illustrated by a plate, with drawings 

 of marked distinctness and beauty by the writer. 



