576 SUMMARY OF CURRENT RESEARCHES RELATING TO 



water in the tube at first, so that the animal may not be destroyed 

 by too strong a rush of water. The water is then emptied out of the 

 tube into a drop of 1 per cent, osmic acid on another slide, and the 

 acid allowed to act for about ten minutes as a maximum. The animal 

 is then stained with Beale's carmine, washed with water, and after 

 gradually hardening in alcohol transferred to oil of cloves. 



Another process is to be recommended for small quick-swimming 

 Protozoa. After it has been ascertained that the water in the watch- 

 glass contains many Protozoa a sufficient quantity of osmic acid is 

 poured in, and the subsequent processes of staining, washing, and 

 transferring to alcohol and oil of cloves are all performed in the 

 watch-glass. The animals are so fixed in the sediment that it is 

 rarely any are lost in sucking off the fluid. Then a drop of the oil 

 of cloves is taken up under the Microscope in a wider tube, and the 

 organisms brought away isolated by the capillary tube and put at 

 once into Canada balsam. 



Although Canada balsam preparations have the advantage of 

 greater durability, yet glycerine is to be preferred for many Protozoa. 

 In particular, Actinosphcerium Eichhornii is much more beautiful in 

 glycerine than in Canada balsam. The frothy condition of the ecto- 

 sarc is shown most clearly, and the contractile vacuoles remain, as 

 in the living state, prominent at the surface of the animal. 



Staining the Nucleus of Living Infusoria.— We are sorry that 

 by the interpolation of the word " erroneously" at p. 281 it was made 

 to appear that M. A. Certes was not justified in claiming as a " new 

 fact " the staining of the nucleus of living Infusoria. The author of 

 the interpolation, to whom we have referred on the subject, informs 

 us that the fact of the note dealing with the living animals had 

 momentarily escaped his attention. 



Double Staining with Carmine and Anilin Green.* — Mr. T. W. 

 Taylor obtains very beautiful results from the following method of 

 using preparations of carmine and anilin green f together. 



The section is immersed from five to ten minutes in the green, 

 and then passed at once into the carmine, in which it remains from 

 one to three minutes, the process being carefully watched in order 

 that the carmine may not stain too deeply. It is then thoroughly 

 washed in absolute alcohol, passed through oil of cloves, and then 

 mounted in solution of balsam in benzole. The use of the benzole- 

 balsam is important, as it has a decided action in fixing the stain, 

 due to the presence of benzole. Two or three drops of each liquid 

 suffice, and the whole operation is performed upon a glass slide, or in 

 a watch-glass. 



The woody parts of the section take a rich carmine, shading into 

 orange, while the pith and light cellular tissue are stained a bright 



* Amer. Mon. Micr. Journ., iii. (1882) pp. 92-3. 



t Carmine stain : carmine 15 gr., ammonia 15 gr., distilled water 2 oz. ; dis- 

 solve carmine in ammonia over the flame of a spirit-lamp, add the distilled water 

 and filter. Green stain : anilin green 5 gr., absolute alcohol 1 oz. 



