ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 707 



paraffin dissolved with turpentine or xylol, the slide is placed in turpen- 

 tine containing a few drops of a solution of picric acid in absolute 

 alcoliol. In a few seconds, nerve-fibres, connective tissue, and muscles 

 are stained yellow. The slide is next to be placed in turpentine con- 

 taining a Jew drops of alcohol, to wash away the excess of picric 

 acid, then in pure turpentine or xylol preparatory to mounting in 

 balsam.* 



Preparing Sections of Spines of Echinus.f — Mr, J. D. Hyatt says 

 that it is much easier to grind down a number of such sections at one 

 time than to grind one singly, and he therefore fills a glass tube with 

 spines, cementing them in place with balsam, and then by means of a 

 circular diamond-saw slices both tube and contained spines into thin 

 discs. A number of these discs are cemented by balsam to a glass slip, 

 and all are ground down together. In order to successfully turn them 

 over to continue the grinding, they are cemented to the first slip with 

 thin balsam. The slip to which they are to be transferred is supplied 

 with thick balsam and inverted over the sections, whereupon, with 

 proper manipulation, the sections will leave the first slip and adhere to 

 the second. He mounts seven or eight sections of spines under one 

 cover, returning them to their desired positions, if displaced in mounting, 

 by inserting under the cover a needle ground flat and very thin upon 

 an emery wheel. 



Examining a Shell-bark Hickory Bud.| — Dr. H. Shimer writes : — 

 Cut a longitudinal section near the middle (a somewhat thick section, 

 1/100 to 1/300 in., is easily cut), transfer it to a slide, apply glycerin 

 with a brush ; after it has pretty well soaked, drain off the superfluous 

 fluid, warm the slide, apply glycerin-jelly, or better, the author's new 

 mounting formula : — Glycerin-jelly, 1 part ; Farrant's medium, 1 part ; 

 glycerin, 1 part, thoroughly mixed. Apjjly a heavy cover-glass, press it 

 down a little, at length seal the edges with cement, and the result is a 

 very beautiful specimen permanently mounted. 



Examine it with a 1 in. objective, the stand being in the sunshine 

 with a piece of sky-blue blotting-paper over the mii-ror for a background, 

 and we have a more beautiful and instructive specimen than a 1/1000 in. 

 section made in celloidin. The arrangement of the leaves and the hairs 

 are all that could be desired. Even the cellular structure can be studied. 

 This process is given, not to supersede other fine methods, but only as 

 an easy method to aid in the study of a beautiful bud. If it is a side 

 bud it will show the origin of the bud in the side of the limb and its 

 progress to the surface. 



White's Botanical Preparations.§— Mr. C. W. Smiley describes the 

 botanical preparations of Mr. Walter White. Though not pretending to 

 take the place of objects mounted in the usual way, yet, being inclosed 

 in a transparent envelope, they are available for immediate examination, 

 either without or with magnification, in many cases even with the higher 

 powers of the Microscope. 



* A.mev. Nat., xxiii. (1S89) pp. 189-90. 



t Jouru. New York Micr. fSoc, v. (1889) p. 44. 



t Amcr. Moil. Micr. Jouru., x. (1889) p. 101. See also p. 130. 



§ T.c, pp. 110-1. 



