l893-] NEW-YORK MICROSCOPICAL SOCIETY. 35 



plasm in the presence of corrosive agents (in some cases, perhaps, 

 this shrinking inside of a cell-wall being the only movement it 

 has shown in life), as well as that due to " irritability," even after 

 "death. The irritating properties of the gold and platinum chlo- 

 rides, and the strong astringent properties of the alums, on which 

 is founded their usefulness in media for other purposes, are par- 

 ticularly objectionable, in my opinion, on account of the corre- 

 fsponding contraction they produce upon protoplasm. Therefore, 

 for this purpose, I am inclined to reject King's fluid for marine 

 algae (alum, mercuric chloride, and sea water) ; Wickersheimer's 

 preservative for algae, lichens, fungi, etc. (alum, common salt, 

 potassium nitrate, potassium carbonate, arsenious acid, distilled 

 water, glycerin, and methyl alcohol); an alga preservative (chloro- 

 form, glacial acetic acid, and distilled water) ; Pacini's preservative 

 for blood corpuscles (mercuric chloride, common salt, glycerin, 

 and distilled water) ; Morehouse's preservative for algce, desmids, 

 volvox, etc. (copper acetate, camphor water, distilled water, 

 glacial acetic acid, and glycerin) ; Meckel's, for protozoa 

 (chromic acid, acetic acid, platinum chloride, and water) ; pre- 

 servative for algae, characeee, and infusoria (salicylic acid, wood 

 vinegar, glycerin, and water) ; preservative for confervae (chloro- 

 form, glacial acetic acid, and water) ; Ripart's preservative for 

 ^pirogyra and other algae (glacial acetic acid, camphor water, and 

 distilled water) ; preservative for algae, desmids, etc. (Deane's 

 •compound, Ralf's liquid, glycerin jelly, and solution of aluminum 

 acetate) ; preservative for entomostraca (carbolic acid, alcohol, 

 and water) ; Goadby's preservative ; boroglyceride (boracic acid 

 in glycerin) ; and a large number of others. 



3. Contraciion by Absorption of Water. — This cuts off at once, 

 it seems to me, the use of all the dehydrating fixatives, hardening 

 solutions and preservatives, e.g.^ those in whose composition 

 either alcohol or glycerin has been used in any proportion what- 

 ever. The fact that some such mixtures have seemed at least 

 comparatively satisfactory to investigators probably shows only 

 that contraction has progressed more slowly and distortion been 

 longer deferred. With half the percentage of the ingredient that 

 is greedy for water, the mounted object is ruined in two years 

 instead of one. 



Notwithstanding the recent recommendation of Klein' for the 



1 Jour. Roy. Mic. Soc. (188^), 140, from Hedwigia. 



