218 



THE AMERICAN MONTHLY 



[November, 



1. Unknown fly in fossil gum 

 copal. iV. T. Veeder. 



2. Transverse section ot" tea-leaf 

 and stem. F. T. Aschman. 



3. Striated muscular fibres, in- 

 jected. T. D. J3iscoe. 



4. Section of cat's tail, injected. 

 G. W. Worcester. 



5,. Conjugation of alga'. E. L. 

 Cheeseman. 



6. Lung of foetus. Chas. K. Wells. 



Box Cw came to hand October 

 31st, with tw^o of Cole's preparations. 

 The objects contained in it are : 



I . Primary tissue. 



z. Epidermal tissue. 



NOTES. 



— We have received a new edition of 

 the catalogue of Mr. Carl Zeiss from 

 Messrs. Emmerich & Son, who have just 

 received a supply of them. The cata- 

 logue is issued in far more attractive style 

 than hhherto, and is much larger than 

 previous editions. It affords a complete 

 list of the microscopical apparatus, in- 

 cluding the objectives, made by Mr. Zeiss, 

 with numerous illustrations. Glancing over 

 the pages we notice many changes and 

 additions. 



Among the additions may be mentioned 

 an apparatus for measuring the growth 

 of plants, devised by Reinke. In addition 

 to the spectral-ocular, so well known, 

 there is now offered a micro-spectral ob- 

 jective, devised by Engelmann for obser- 

 vadons on the action of spectral colors 

 upon microscopic objects. The device is 

 fitted beneath the stage of the microscope, 

 and projects a spectrum upon the object 

 in the field of view. The Abbe analysing- 

 ocular, hitherto advertised, and the polar- 

 izing apparatus connected with it, is no 

 longer made, owing to the difficulty of 

 obtaining sufficiently good calc spar for 

 the prisms. Two forms of apparatus for 

 photo-micrography are described, with an 

 illustration of a method of quickly uniting 

 the microscope tube and camera with a 

 light-tight joint. 



The catalogue is in German, Mr. Zeiss 

 might find it advantageous to arrange 

 with the Messrs. Emmerich for an edition 

 in English. 



— Mr. Zeiss still prefers cedar oil (from 

 Junipcrns Vtrgitiiana) for his homogene 



inmersion objectives, and he has lately 



succeeded in overcoming the most serious 

 objection to its use, its extreme fluidity. 

 He now offers the oil in a thickened con- 

 dition, and with a refractive power almost 

 identical with that of cover-glass. We 

 notice that Mr. Zeiss has ceased to make, 

 e.xcept by special order, the water immer- 

 sion objective of 0.75 mm. focus, since 

 experience has shown that such a short 

 focus in a water immersion lens offers no 

 advantage that cannot be more effectively 

 obtained by the use of the y^^-inch homo- 

 gene immersion. 



— The September number of the Kan- 

 sas City Review, an excellent magazine 

 for general reading, published at Kansas 

 City, Mo., contains its usual variety of 

 interesting and valuable articles. The 

 Review comes to us in a new dress, and 

 is henceforth to be an illustrated monthly 

 magazine, but the price is only $2.50 per 

 year. 



— The San Francisco Microscopical So- 

 ciety seems to be most active of any dur- 

 ing the summer months. We receive re- 

 ports of its proceedings regularly from the 

 Secretary, Mr. A. H. Breckenfield. At 

 a meeting in July, Dr. J. M. Selfridge read 

 the paper of the evening, entitled 'Bac- 

 teria and Their Relation to Health and 

 Disease.' He reviewed the grounds upon 

 which the advocates of the germ theory 

 rest their case. Extensive quotations 

 from the writings of Koch, Pasteur, Cohn, 

 Sternberg and others were cited, and their 

 experimental work alluded to. These em- 

 inent authorities, and many others in sym- 

 pathy with them, claim that it has been 

 demonstrated beyond all reasonable ques- 

 tion, that certain diseases, such as an- 

 thrax, fowl-cholera, tubercular phthisis, 

 etc., are produced be the parasitic micro- 

 organisms, bacteria. Dr. Selfridge next 

 stated his own view of the case, which is 

 that bacteria are the result but not the 

 cause of the decomposition of organic sub- 

 stances. He fortified his position by quot- 

 ing extensively from the writings of scien- 

 tists holding similar views and by pointing 

 out what he considered the fallacies in 

 reasoning of his opponents, and the er- 

 roneous deductions drawn by them from 

 their experiments. He argued that in . 

 order to prove that one thing is the cause 

 of another, it must be shown that the 

 cause was in active presence before the 

 thing produced was manifest. In the 

 case of bacteria, therefore, he held that 

 it must be shown that they are in the 

 blood of a given case before the disease 

 manifests itself. For, if they be not pres- 



