650 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



] 35 mm., and the height to the lower border of the neck about 150 mm. 

 There is an opening at the top of the bell-jar, and this is closed by an 

 indiarubber stopper, on the bottom of which is glued an ordinary cover- 

 glass. The cover-glasses the films on which are to be fixed are laid 

 on a glass plate and covered by the bell-jar. The stopper is removed 

 and a drop of formalin is placed on the attached cover-glass at its lower 

 end, and the stopper immediately replaced. The films, which must be 

 quite dry, are exposed to the vapour for 15 minutes or more, but not 

 longer than 30 minutes. The films should be thin, as thick ones are 

 liable to crack. 



Mounting of Mosquitos.*— Dr. G. M. Giles recommends the following 

 method for mounting mosquitos. As microscopical specimens, mosquitos 

 should be mounted dry, and for this purpose Carpenter's foraminifera 

 slide is best suited. This consists of a wood slip 3 in. by 1 in. by T V in- 

 thick, with a hole about § in. in diameter in the middle. This hole is 

 converted into a cell by means of a cover-glass secured by gummed 

 paper. The mosquito is spread out in the cell, which is then closed by 

 means of another cover-slip, secured in the same way. 



By this dry-mounting method the colour characters, only visible by 



reflected light, are preserved. When wet or balsam-mounted the specific 



distinctions are lost. 



(6) Miscellaneous. 



Apparatus for Ascertaining the Effect of Disinfectants.! — Dr. 

 Piorkowski describes an apparatus (fig. 180) which he has found very 

 valuable for determining the effect of disinfectants. It consists of a 

 metal box made air-tight when closed by means of a rectangular bayonet 



Fig. 180. ■ 



fastening.; About half-way down the well is fitted a removable wire net 

 tray. In tne front (and at both end,s if necessary) is a small tube which 

 can be closed with a metal cap. Through this tube the disinfectant in 

 ihe form of spray is introduced and made to play on the various objects 



* Brit. Med. Journ., 1900, ii. pp. 459-60. Cf. this Journal, ante, p. 527. 

 t Centralbl. Bakt. u. Par., 1" Abt, xxvii. (1900) pp. 609-10 (1 fig.). 



