670 SUMMARY OF CUREENT RESEARCHES RELATING TO 



of a small number of " chloride of calcium jars," i. e. tall slender jars 

 with an opening near the base, which are connected by means of " three- 

 way " tubes with a common tube of small size. The latter tube is inserted 

 into the side of a microscopic cell made of soft rubber, firmly cemented to 

 the slide and provided with an inflow and an outflow. The object is held 

 beneath the glass cover either by delicate glass floats or by glass threads 

 fastened by wax. When the object is in situ the liquid is made to flow by 

 opening one of the cocks or one of the way tubes. The stream of fluid 

 may be made slow or rapid, and one fluid may be substituted for another. 



The same apparatus may be used for difiereutial staining, for plasmo- 

 lytic investigation, and for the cultivation of organisms under different 

 conditions of nutriment. 



Modes of preparing Ova.* — Dr. H. Henking, in his investigations into 

 the development of the Phalangida, adopted various methods of preparing 

 the ova ; the animals were sometimes killed with boiling water, and left in 

 it for some time for the albumen to coagulate ; they were then hardened in 

 successive strengths of alcohol up to 80 per cent. The ova were never placed 

 direct in alcohol, in consequence of the shrinking caused by such a process. 

 Other specimens were killed with ether, the back laid open, and the animals 

 placed in Flemming's chrom-osmic-acetic acid, or in Kleinenberg's picrosul- 

 phuric acid for some hours before removal to alcohol. Eggs that had been 

 deposited were treated with hot water, and with Flemming's fluid, as well as 

 with hot and cold chromic acid, picrosulphuric acid, &c. The best staining 

 reagents were found to be Grenacher's borax-carmine, Hamann's neutral 

 acetic acid carmine, and eosin-hsematoxylin. Before imbedding, the eggs on 

 being taken from absolute alcohol were placed in a mixture of Isergamot oil 

 and absolute alcohol, then in pure bergamot oil, and then in a warmed solution 

 of paraffin in bergamot oil, and finally in quite pure paraffin. By the aid of 

 Spengel's microtome sections from 1/80 to 1/150 mm. thick were prepared. 



New Method of distinguishing Vegetable from Animal Fibrcf — 

 Dr. H. Molisch's process depends on the application of the two new re- 

 actions for sugar lately discovered by the author 4 — About 0-01 gram of 

 the sample, previously well boiled and washed with water, is mixed first 

 with 1 ccm. of water, then with two drops of an alcoholic solution of 

 a-naphthol (15-20 per cent.), and finally with an equal volume of concen- 

 trated sulphuric acid. In the case of vegetable fibre the solution assumes, 

 immediately after shaking, a deep violet colour, the fibre being dissolved. 

 If, however, the fibre is of animal origin, the liquid assumes a colour 

 varying from yellow to reddish-brown. By substituting a solution of 

 thymol for a-naphthol a fine carmine colour is obtained in the place of the 

 violet. 



The author has successfully applied this test to different vegetable 

 fibres, such as cotton, hemp, jute, china-grass, &c. ; also to the cellular 

 tissues of wood, cork, and fungi. Moreover, in the case of dyed fabrics 

 the colouring matters do not appear to interfere with the success of the 

 reaction. 



Mode of examining Mucous Menibranes.§ — Prof. L. Eanvier describes 

 the following method of studying the membrane which invests the retro- 

 lingual sac of the edible or the grass-frog. The membrane is detached 

 and then extended on the disc of Eanvier's moist chamber in such a 



* Zeitscbr. f. Wiss. ZooL, xlv. (1887) pp. 88-90. 



t Dingler's Poly tech. Jouru., cclxi. (18SG) pp. 135-S. Cf. Joiirn. Chem. Soc. Lond., 

 Abstr., 1886, p. 1088. J See tbis Journal, ante, p. 344. 



§ Comptcs Kendus. civ. (1887) pp. 819-20 (1 bg.). 



