ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 255 



spectively. Incubate at 36° C. Take samples every four hours, and 

 inoculate Endo's mediumiand litmus-lactose agar plates. Water : 50 com. 

 of the water to be analyzed is added to tubes containing 50 ccm. pepton 

 water containing y^Vo ^^^ Wo^ malachite-green respectively ; then 

 proceed as above. 



(2) Preparing- Objects. 



Embryonic Development of Trichogramma evanescens : Monem- 

 bryonic Egg-parasite of Donacia simplex.* — J. B. Gatenby used the 

 following technique. As the egg of Donacia is covered by a thick 

 chorion sectioning is a difficult business. The parasitized egg-masses 

 were preserved in Petrunchekewitsch with a little more nitric-acid than 

 usual. A mixture of Petrunchekewitsch and Bouin gave about equal 

 results. In some cases the eggs were pricked and the whole thrown 

 into picro-nitric. After some trials Petrunchekewitsch was almost 

 exclusively used. In using this fixative it is not necessary to prick the 

 eggs. Ordinary preservatives will not penetrate the chorion. The eggs 

 were left overnight in the Petrunchekewitsch and washed out in 70 p.c. 

 alcohol. When in xylol the eggs were pricked with a fine needle and 

 placed in the paraffin bath. The eggs were cut into their groups, 5 fx in 

 thickness on a Jung microtome, each section being painted with celloidin 

 and ether. By staining overnight in iron-hsematoxyUn a suitable 

 differentiation could be got while Ehrlich and the carmines were useless. 

 In some cases alternate slides were counter-stained in orange Gr or 

 dilute acid fuchsin. 



Treatment of Tuberculous Sputum by Pyridine.! — M. Giraud and 

 E.Derrien give the following method for rendering sputum homogeneous. 

 It is mainly intended for the examination of tuberculous sputum. To 

 10 c.cm. of sputum are added 15 ccm. of cold pyridine. The mixture is 

 then shaken well in some vessel and afterwards allowed to stand for five 

 minutes to hours. When liquefied the mixture is centrifuged. The 

 deposit is used for making films in the usual way, but if there should be 

 a surface pellicle this also should be examined. The films when dry are 

 stained by the Ziehl-Neelsen method. The authors find that this 

 procedure gives very satisfactory results. 



Spreading- Blood-films.J — L. Tribondeau recommends the use of a 

 scissors' blade or a straight-edged knife for spreading blood on slides. 

 This procedure does not appear to possess advantages over those obtained 

 by older methods, e.g. short edge of a slide, cigarette-paper, strip of thin 

 rubber, glass roller, etc. It is chiefly a question of the manipulator. 

 The writer of this notice, who has had many assistants in his time, has 

 remarked that only a few of these had the deft use of their fingers — 

 these made good blood-films ; about the rest is silence. 



* Quart. Journ. Micr. Sci., Ixii. (1917) pp. 149-87 (3 pis.), 

 t C.R. Soc. Biol. Paris, Ixxix. (1916) pp. 376-7. 

 X C.R. Soc. Biol. Paris, Ixxix. (1916) pp. 1011-2. 



