1896 THE MICROSCOPE. 27 



characters undergoes but slight changes, why could not 

 the same points be made use of in selecting yeasts for bak- 

 ing purposes ? 



Besides, looking at it from the point of view of the 

 makers of pressed yeast, a better yield of yeast should 

 result from a careful selection of a cultivated species. 

 Moreover, when people in general understand the action 

 of yeast and fermentation as a whole, better, the 

 prejudices held by some people against yeast will be abol- 

 ished, and the sensational "scares" that appear occasion- 

 ally in the newspapers will cease, as will also the pseudo- 

 scientific communications such as those published in the 

 " Century " a year or so ago from a well-known physician 

 connected with the New York Board of Health. 



QUESTIONS ANSWERED. 



NoTR. — Dr. S. G. Shanks, of Albany, A' )' . I;iii({ v ronsents to receive all sorts of ques- 

 tions relating to 7nicroscopy,wh the a^k.ut h\ f> o/ess'nnals or amateurs. Persons of au 

 f ades of experience, from tlie lu-i^i-. nfi nf.i'n </. << < c ?>' h„nte to the benefits of this d,f-i'- 

 nient. The questions are nuiubei • d /or lumie ejetei,ce. 



234 How shall I make hay or vegetable infusion, for animal- 

 cides, etc f K W. P. 



Cut some hay or other vegetable matter into small fragments, 

 cover it with tepid water and let it stand in a warm place for 

 two or three days. Water that has contained cut flowers, is 

 teeming with infusoria, especially if at all putrid. 



235 Can you inform me who is the successor of professor H. L. 

 Smith, the Diatomistf D. A. N. 



Dr. D. B. Ward, 27 Garden Street, Pougkeepsie, N. Y. has all 

 the diatom material collected by Prof. H. L Smith. 



236 Kindly inform me of the most recent work on preparing and 

 mounting, containing specific and detailed methods, general informa- 

 tion, etc. — in one volume or single. C. M. M. 



Practical methods in microscopy — b}' Chas. H. Clark. — Pub. 

 D. C. Heath & Co. 



