112 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



then 50 c.cni. of strong ammonia poured over it. The blue liquid 

 which passes through is poured back again several times over the 

 precipitate in order to obtain all the copper hydroxide and leave only 

 the insoluble barium sulphate. The fluid thus obtained is found to 

 have a strong solvent action on cotton. 



Apparatus for Observing- the Suction of Insects.* — G. Zirolla has 

 devised the following apparatus (fig. 18), by means of which an isolated 



8 



r^\ 



Fig. IS. 



insect can be retained whilst it sucks blood from a healthy or infected 

 man or animal. It consists of a small glass tube C, which is inclosed in 

 a nickel vessel provided with an easily movable disk, by which the tube 

 can be closed or opened. This tube is hitched to a nickel stand D, 

 which at its base has an iris-diaphragm with a convex lower surface. 



Centralbl. Bakt., lte Abt. Orig., xlviii. (1908) p. 173 (1 fig.). 



