180 



THE AMERICAN MONTHLY. 



[September. 



length. The worm, when dropped into 

 a cup of water, exhibited vigorous Ufe 

 throughout its entire length. It is about 

 ^^ of an inch in diameter, white, ringed, 

 and tapers at each extremity like the 

 earthworm. The grasshopper, when cap- 

 tured, seemed to be in normal physical 

 condition. If any of your readers have 

 ever found so large a living creature dom- 

 iciled in so small a tenement, I would be 

 pleased to hear from them. 



Edward G. Day. 

 Riverside, Conn. 



NOTICES OF BOOKS. 



The Formation of Poisons by Micro- 

 organisms. A Biological Study of the 

 Germ Theory of Disease. By G. V. 

 Black, M. D., D. D. S. Philadelphia: 

 P. Blakiston, Son & Co., No. 1012 Wal- 

 nutStreet. 1884. (pp.178. Cloth,$i.5o.) 

 This volume contains a series of lec- 

 tures delivered before the Chicago Col- 

 lege of Dental Surgery. The first part 

 begins with a study of the germ theory of 

 disease, in which the author displays con- 

 siderable familiarity with the literature of 

 the subject. Evidence in support of the 

 germ theory is briefly given, the nature of 

 miasm and contagion is discussed, the 

 views of different recognized authorities 

 are concisely stated, and the results and 

 evidence are finally summed up in the 

 third lecture, which concludes the first 

 part. 



The second part, the author says in his 

 preface, ' was written because I had some- 

 thing to say that I thought ought to be 

 said at the present time.' It begins with 

 a lecture on the Relation of Micro-Organ- 

 isms to the Production of Disease. The 

 author holds to the view that the organ- 

 isms of disease produce poisonous com- 

 pounds in the body, and in this way be- 

 come the cause of disease. He goes on 

 to consider the physiological phenomena 

 of life at length, considering especially 

 the action of ferments in digestion, and 

 finally the production of alkaloids in the 

 system and the growth of bacteria. The 

 seventh and last lecture treats of poisons, 

 and particularly the poisons produced by 

 micro-organisms. So little is yet known 

 about this subject it is scarcely possible 

 that the author could reach any very posi- 

 tive conclusions. It is principally a mat- 

 ter of conjecture how the organisms of 

 disease act upon the system. The book 

 is well worth reading as a good summary 



of the arguments in support of the views 

 set forth. 



In the Appendix is a chapter on Dental 

 Caries and its relations to the germ the- 

 ory of disease, in which the view is taken 

 that there is a kind of ferment formed 

 which, as we understand the matter, may 

 or may not be the product of micro-organ- 

 isms, but frequently associated with them, 

 which destroys the teeth. 



Microscopic Observations. By Thomas 

 Taylor, M. D. Internal Parasites in 

 Domestic Fowls and Butter and Fats. 

 Washington : Government Printing Of- 

 fice. 1884. 



This is a small pamphlet of seven pages 

 and one colored plate, illustrating the ap- 

 pearance of different fats under polarized 

 light. Those who are interested in the 

 subject would do well to write to Dr. Tay- 

 lor for a copy of the pamphlet. 



How to Grow Fine Celery. A new 

 method. By Mrs. H. M. Crider. York, 

 Pa.: H. M. Crider, publisher. 1884. 

 (Pamphlet, pp. 16. Price, 25 cents.) 



Exchanges. 



[Exchanges are inserted in this column without 

 charge. They will be strictly limited to mounted ob- 

 jects, and material for mounting] 



Echinus spines of various species offered to any 

 person who will send in return three good sections 

 oi the same. 



Box 630, Washington, D. C. 



Wanted — Diatoms on seaweeds and in muds, from 

 all the tropic seas. Offered a large quantity of fine 

 selected diatoms and other slides, or cash. 



J. C. RINNBOCK, 

 14 Simmering, Wien, Austria. 



Will exchange well mounted slides for others well 

 mounted. 



H. H. PEASE, 

 1271 Broadway, N. Y. 



Slides of fresh water algse, desmids, bacteria, infu- 

 soria, &c., lor good pathological or other interesting 

 slides. Lists exchanged. 



J. M. ADAMS, 

 Watertown, N. Y. 



Material for mounting of all kinds wanted in ex- 

 change for other first-class unmounted objects in great 

 variety. 



M. A. BOOTH, 

 Long Meadow, Mass. 



Will exchange very thinly cut and well-stained his- 

 tological and pathological slides for other histological 

 and pathological slides. Will also exchange a limited 

 number of histological torother slides of various kinds. 

 H L. WHITNEY, M. D., 

 German Hospital, Girard ave. and 21st St., 

 Philadelphia, Pa. 



Will exchange good slides of micro-fungi, various 

 Diatoms in situ on algse, chemical crystals, and a fine 

 selection of stellate hairs on leaves of plants, for other 

 good slides. 



JAS. E. WHITNEY. 

 Rochester, N. Y. 



