ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 59] 



feet is put on. Water is first run through, and afterwards the different 

 staining fluids. This procedure is tedious, and involves great loss of 

 material. A better method is to lay a drop of the culture fluid on a 

 slide or on a cover-glass, and kill the animals with osmic acid vapour or 

 by means of a drop of some other fixative such as cold saturated subli- 

 mate solution, Hermann's fluid, or picrosulphuric acid. The fluid is 

 allowed to evaporate in the air until only a trace of moisture remains. 

 The slide or cover-glass is then placed in absolute alcohol for 24 hours, 

 to which, if sublimate have been used, some tincture of iodine must be 

 added. The preparations are then treated like stuck-on sections, and 

 there is no considerable loss of material. If the culture fluid contains 

 a large quantity of bacteria, these organisms may be washed off with 

 alcohol when the layer has not completely dried. 



Fixing Blood Preparations with Chloroform.* — 0. Josue has found 

 chloroform to be an excellent fixative for blood-films. The film is pre- 

 pared in the usual way, dried in the air, and then immersed in chloro- 

 form for about two minutes. It is then allowed to dry, and afterwards 

 stained and mounted. 



; ^Method for Examining Ocelli of Insects. | — W. Eedikozew adopted 

 the following procedure. Immediately after decapitation the heads were 

 fixed in picrosulphuric acid, picro-acetic acid, sublimate, or in sublimate 

 with 2 p.c. acetic acid. After washing out the fixative, the objects were 

 preserved in 70 p.c. alcohol. The preparations were stained with a 

 combination of borax-carmine and Lyons-blue, by immersing the object 

 for 24 hours in borax-carmine and incubating at 45°, and then extracting 

 for one or two hours with 1 p.c. hydrochloric acid. The mass was then 

 imbedded and sectioned. The sections were after-stained for one or 

 two minutes in £ p.c. Lyons-blue solution in 70 p.c. alcohol. 



For isolating the ocelli the following maceration fluids were used. 

 NaCl solution with 0*2 p.c. acetic acid, incubated at 45°; 0*005 p.c. 

 chromic acid ; 10 p.c. alcohol ; also eau de Javelle much diluted. 

 Pigment was removed by means of 25 p.c. nitric acid or by a mixture of 

 chromic and acetic acid. For softening the cuticula for sections, eau de 

 Javelle, though satisfactory, requires to be used with great care, and the 

 mouth and the opening in neck must be stopped with paraffin. 



Method of Finding Tubercle Bacilli in Sputum.:}: — De Lannoise 

 and A. Girard place the sputum in about 10 times its bulk of eau de 

 Javelle diluted to one-third, and shake the mixture energetically from 

 time to time. It is then allowed to sediment for 24 hours, or better is 

 centrifuged. To the sediment, which amounts to about 2-3 ccm., are 

 added 5 or 6 drops of normal NaHO or KHO. In this way NaCl is 

 formed. The tube is then filled up with sterilised water and centrifuged 

 again. The sediment is spread on slips or slides and treated in the 

 usual way. 



Behaviour of Spores and Fat-Drops in Bacteria to Eau de Javelle 

 and Chloral hydrate Solution. § — Prof. A. Meyer has already pointed 



* CE. Soc. Biol., liii. (1901) p. 642. 



t Zeitschr. wias. Zool., lxviii. (1900) pp. 581-624 (2 pis.). 



X Archiv. Gen. de Med., 1900, Supplement to Out. No. 



§ Centralbl. Bakt., 1" Abt., xxix. (1901) pp. 809-10. Cf. this Journal, 1900, p. 370. 



