ZOOLOGY AND BOTANY^ MICROSCOPY, ETC. 165 



Preparing Lactarius to show Branched Laticiferous Vessels.* — Dr. A. 

 Weiss finds that pieces of Lactarius deliciosus should not be kept too long 

 in spirit, and that sulphuric acid shows the course of the vessels very 

 plainly, the contents of the tubes assiiming quickly a blue-black colour. 

 The surrounding tissue being greatly aifected by the reagent, the latici- 

 ferous vessels appear still more clearly, and slight pressure on the cover- 

 glass serves to separate them for some distance. Iodine water imparts 

 to the tubes and their contents a trace of green, which is rendered more 

 intense by potash, and the juice appears in large dark-orange coloured 

 drops. The colour afterwards passes into brown. Ferrocyanide of potash, 

 sulphocyanide of potash, nitrate of silver, bleach the juice. Platinum 

 chloride, cobalt oxide, chromic acid, and potassium bichromate have no 

 effect; gold chloride stains the vessels blue-black, the hyphse greenish 

 yellow. Sulphuric acid stains the contents of the vessels yellow, yellowish 

 green, greenish black, and finally blue-black ; the contents of the hyphal 

 filaments rose-red. Iodine solution brings out a very dark almost black 

 colour in the vessels. 



Solution of Starch in Leaves."]" — M. L. Brasse describes the manner 

 in which a diastatic ferment can be extracted from green leaves. The 

 leaves are bruised in a mortar and covered with cold water ; after twenty- 

 four hours they are pressed, 1^ volumes of 90'^ alcohol added, and the 

 juice filtered. The same quantity of alcohol is again added to the filtrate 

 and the precipitate thrown on a filter, and rapidly washed with alcohol 

 of 65°. The diastase is obtained in solution by dissolving the washed 

 precipitate in water and filtering. 



New Reagent for Coniferin.ij: — Dr. H. Molisch describes the mode of 

 preparation and action of a new reagent for coniferin. We have hitherto 

 been indebted to the reaction vpith phenol and hydrochloric acid for the 

 identification of coniferin in plant tissues. A section containing coni- 

 ferin, one of pine- wood for instance, if moistened with this reagent, gives 

 in direct sunlight an intense yellow-green or blue-green or sky-blue. By 

 the aid of this the general diffusion of coniferin in lignified tissues was 

 recognized firstly by F. Tiemann and W. Haarmann, and then by v. Hohnel 

 and Singer ; in fact, this glucoside is stated to be always present in woody 

 tissues or in lignin. During the study of two new sugar reactions,§ the 

 observation was made that thymol colours woody tissue a striking blue- 

 green in the presence of concentrated hydrochloric acid. 



The observation was carried out as follows : — A 20 per cent, solution of 

 thymol in absolute alcohol was first prepared ; with this a section of 

 pine-wood was moistened, and as much hydrochloric acid added as would 

 fill the space between the cover-glass and the glass bearing the object. 

 In a few minutes a green colour developed, which soon turned to blue- 

 green or blue ; or, if the above had taken place in direct sunlight, the 

 colour would be almost immediately a deep sky-blue. 



The author then quotes from a paper of T. and D. Tommasi, published 

 in 1881, which pointed out the fact that a greater intensity of colour is 

 obtained when working the phenol-hydrochloric acid reaction, if previously 

 some potassium chlorate be added to the acid. Taking advantage of this 

 result, the following reaction is used by the author as being the most 



* SB. K. Akad. Wiss. Wien, xci. (1885) pp. 166-202 (4 pis.). 



t Aun. Agrouom., xii. pp. 200-3. See Journ. Chem. Soc. Lond. — Abstr., 1. (1886) 

 p. 827. 



X BtT. Deutsch. Bot. Gesell., iv. (1886) pp. 301-5. § See mfra, p. 1G9. 



