1892. j NEW-YORK MICROSCOPICAL SOCIETY. 31 



ever, at the right moment, the histological details will be preserved. 

 The Stentors may then be washed in alcohol of 70 per cent, and 

 stained in a rose-red solution of borax-carmine in hydrochloric al- 

 cohol of 70 per cent. A satisfactory stain will be obtained in about 

 one hour's time. The Stentors being likely to contract if trans- 

 ferred from absolute alcohol directly to oil of cloves, it is advis- 

 able to place them in oil of cloves strongly diluted with absolute 

 alcohol, which latter is allowed to evaporate. This proceeding 

 must be followed when mounting the specimens in Canada bal- 

 sam. If all the above-mentioned details are adhered to, better 

 slides will be obtained than have been produced by any other 

 method. 



2. Spirostoinum teres. — These extraordinarily sensitive infu- 

 sorians may be treated in the same manner. 



3. Carchesium polypiiiimi. — The difficulty in preparing Carche- 

 siiim and many other Vorticellidse lies in the fact that the muscles 

 of the peduncles strongly contract when brought in contact with 

 the preserving liquid, in consequence of which the individuals of 

 a colony are drawn together and the natural bell-shaped form 

 becomes rounded. To overcome this place the Carchesia in a 

 o. 2-per-cent solution of hydrochloric hydroxylamine. The pedun- 

 cles cease their periodic contractions after one or two minutes, 

 and remain distended. After about five minutes the cilia move 



■more slowly, and ten minutes later the individuals are ready to 

 be killed, like the Stentors, by means of picric-acetic acid. 



4. Hydra grisea. — Although this object is a comparatively easy 

 one to prepare with any good paralyzing agent, I wished to try 

 the hydroxylamine-poisoning process, in order to study the effects 

 it would have on all the different muscles. Besides, the effects on 

 Hydra of a 0.25-per-cent solution of hydroxylamine chloride are 

 such that not only the body proper remains distended, but the 

 mouth also sometimes remains open. 



5. Dendroccelum lacteum. — In spite of the fact that very good 

 results in preparing sections of Planaria may be obtained with the 

 use of Lang's solution, the latter is unfit for mounting whole speci- 

 mens, because the usually thick and massive animals, which must 

 be pressed for this purpose, cannot become flattened after they 

 have become hard. It is therefore necessary to place the live 

 animal under the cover glass, press it slightly, ^nd then flow in 



