ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
531 
Copper salts produce a faint red coloration of tlie medium. 
Cultivations from “typhoid” stools by this method showed deep 
black discoloration of the medium, and in Petri’s capsules each colony 
was stained black, and without liquefaction of the gelatin. 
(2) Preparing- Objects. 
Examination of Eggs of Limax maximus.* — Mr. F. L. Washburn 
found the most satisfactory procedure was to quickly open the body- 
cavity of a laying slug, and placing the animal for one minute into a 
boiling hot solution of corrosive sublimate ; then to transfer to water, 
remove eggs from oviduct, and shell them. The vitellus was allowed to 
remain in distilled water 2 minutes, then transferred to 35 per cent, 
and 50 per cent, alcohol for 3 minutes each, and then permanently 
preserved in 70 per cent, alcohol. For examination of eggs in toto, 
Czokor’s alum-cochineal gave, as a rule, good results. Picrocarminate of 
lithium was also found to be excellent, on account of its differentiating 
nuclear structures. For section staining on slide, safranin was used for 
2J- minutes followed by acid (1/2 per cent, hydrochloric) alcohol of 90 
per cent, for 7 to 10 minutes. 
Freshly laid eggs placed for 5 minutes in Fol 99 (1 per cent, 
chromic 25 vols., 2 per cent, acetic 50 vols., water 25 vols.) were 
shelled in water ; the vitellus was in the same solution for 5 minutes, 
water 10 minutes, and 35 per cent, and 50 per cent, alcohol 5 minutes 
each, 70 per cent. 30 minutes, and 90 per cent, ad libitum; the results 
were good, taking picrocarminate of lithium very well, if left long 
enough in stain. They all took borax-carmine very well. Both of these 
stains did well after the eggs were immersed in chromic 1/3 per cent, 
for 10 minutes, then shelled in a large quantity of water, vitellus in 
chromic 1/3 for 4 minutes, and water and grades of alcohol as before. 
For permanent preservation of whole eggs it was found satisfactory 
to use 1 per cent, osmic acid for 5 minutes, and Merkel’s fluid for 
4 hours; after shelling, water and grades of alcohol, 2 minutes each 
to 70 per cent, alcohol. 
Examination of Tentacular Nerves of Helix pomatia. j — Dr. P. 
Samassa worked only with fully extended tentacles ; these he placed 
in a 2 per cent, solution of bichromate of potash ; for four days a 
tentacle was laid in a mixture of 4 parts of 2 per cent, bichromate of 
potash and one part 1 per cent, osmic acid, and then for not more than 
a day in 3/4 per cent, solution of silver nitrate ; 6 or 8 hours will 
generally be found enough to sufficiently blacken the fibres. Special 
care was taken to cut the object as soon as possible after removal from 
the silver solution ; it was not hardened in alcohol, but in chloroform, 
and sections of 25 /x were obtained an hour after removal from silver. 
Although the author was unsuccessful with Golgi’s methylen-blue 
method he does not despair of ultimate success. 
Making and Preserving Specimens of Bacteria for Museum Pur- 
poses. t — Dr. C. Kriickmann highly commends the use of formalin for 
* Amer. Natural., xxviii. (1894) pp. 528-31. 
t Zool. Jalirb. (Anat. Abth.), vii. (1894) pp. 584 and 5. 
+ Centralbl. f. Bakteriol. u. Parasitenk., xv. (1894) pp. 851-7. 
