222 



Journal of Applied Microscopy. 



is that it can determine in twenty-four 

 hours whether the eggs are good or not 

 and apply the remedy, while without it, 

 especially in the case of unimpregnated 

 eggs, it is necessary to wait until the sea- 

 son is nearly over before knowing the 

 result, and in the meantime millions, 

 perhaps, of eggs are lost which should 

 have been saved. The writer frequently 

 uses the telegraph in calling delinquent 

 spawn-takers to task, and believes that 

 it has paid well on the investment. 



Aside from examining the eggs to de- 

 termine their quality, the microscope can 

 be made of use almost daily while eggs 

 and fry are in the house. Many little 

 emergencies arise when it is desirable to 

 make a closer examination of eggs or fry 

 than can be made with the unaided eye, 

 and it soon becomes a second nature to 

 resort to the microscope. 



To illustrate: at the Put-in-Bay sta- 

 tion, one morning last April, it was dis- 

 covered that the pike-perch eggs were so 

 light in the jars that it was difficult to 

 keep them from flowing out, although the 

 water had been shut down to a consider- 

 able extent. The microscope revealed the 

 fact that colonies of infusoria — mainly 

 the species Carchesium, with a few Vor- 

 ticellae — were so common that it was dif- 

 ficult to find an egg without one or more. 

 The eggs were thoroughly feathered, thus 

 breaking off the slender stems by which 

 the infusoria were attached, when they 

 worked as well as ever, and no harm 

 was done further than that incident to 

 the handling of this very tender egg. I 

 will state, incidentally, that this phen- 

 omenon has never occurred before at the 

 Put-in-Bay station or elsewhere, to my 

 knowledge. L. b. E. 



Notes on Culture Media. 



Dr. Erwin F. Smith gives the following 

 list of culture media which he has found 

 useful for the differentiation of species: 



1. Uschinsky's solution. 



2. Tubes of standard nutrient agar 

 with the addition of 10, 20, and 30 per 

 cent, of grape sugar. 



3. The same with 10, 20, and 30 per 

 cent, of cane sugar. 



4. Nutrient starch jelly with and 

 without various sugars, alcohols, etc. 



5. Cylinders of cocoanut flesh in dis- 

 tilled water. 



6. Cylinders of white or yellow turnips 

 in distilled water. 



7. Cylinders of carrot in distilled 

 water. 



8. Cylinders of white sugar beet in dis- 

 tilled water. 



9. Potato cylinders standing in several 

 cubic centimeters of distilled water (for 

 prolonged growth). 



10. The extension of tests with fermen- 

 lation tubes to include, in addition to 



grape, cane, and milk sugar, the follow- 

 ing substances: fructose, galactose, mal- 

 tose, dextrine, mannlte, and glycerine. 



These crude vegetable substances con- 

 tain very different quantities and kinds 

 of nutrient substances, and the variety 

 offered enables one to determine the 

 peculiarities of the germs, which, when 

 once discovered, may be studied by more 

 exact methods. e. M. Buack. 



Proc. Am. Asso. Adv. Sci., Vol. xlvil, 189S. 



Bacteriological and Chemical Studies of 

 Sauer-kraut. 



The fermentation of white cabbage to 

 saur-kraut is caused by Bacterium bras- 

 sicae Lehm and Conrad — a close relative 

 of Bacterium coli, according to Eugene 

 Conrad. In addition, two species of 

 yeasts were found, one closely related to 

 Saccharomyces cerevisiae, the other to S. 

 minor. The acid thus produced by the 

 bacterium increases up to a certain point, 

 and then remains constant. It produces 

 aethylic lactic acid and the following 

 gases, CO., H, and CHj. The gases H 

 and CH4 occur in greater quantity than 

 CO2. The yeasts furnish the alcohol 

 necessary to form this acid. If cabbage 

 is fermented with the yeast alone, a dis- 

 agreeable butyric acid odor is produced. 

 The yeasts counteract these injurious 

 properties. L. H. Pammki,. 



Archiv. f. Hyg. 84 : 56. 



Rapid Hardening of Sputum. 



C. Ritter recommends the following 

 rapid drying and hardening of sputum 

 and blood upon slides. A glass dish or 

 tray on blocks to support slides was used, 

 or a glass dish with glass supports on 

 side for slides may be made. These may 

 be used to hold as many slides as desired. 

 The glass tray contains a small quantity 

 of either osmic acid or formalin. The 

 sputum is placed on the slide and then 

 with face down is put on the bench. The 

 dish is then covered. Hardening pro- 

 ceeds very rapidly, after which the 

 specimen may be stained and mounted. 

 L. H. Pammel. 



Zeitscher, f. Wissensch. Mikroskopie 18 : 159-61 

 f. 1-2. 



Different Gelatine Media and Bacteriolog- 

 ical Water Analysis. 



Korn states that the peptone-water- 

 salt-gelatin Is much better for the devel- 

 opment of water bacteria than boullion 

 gelatin. More germs developed in the 

 former than in the latter. Good develop- 

 ment also occurred when salt was absent. 

 The high percentage of salt in ordinary 

 media, as well as grape sugar and 

 glycerine, acted unfavorably on the 



