234 



THE AMERICAN MONTHLY 



[December, 



The Striae of Diatoms on the Mol- 

 ler Probf-Phitte. 



The following table is presented 

 for convenience of reference. It 

 was prepared a number of years ago 

 — the date we do not remember, but 

 it is of no great consequence, as we 

 are not aware of any corrections of 

 the numbers given in the last column. 



— EupoDiscus Argus, - - . . 



1 Triceratium Favus, . - . . 



2 PiNNULARIA NOBILIS, . - - . 



3 Navicula Lyra Var. , - - . 



4 Navicula Lyra, - - . . , 



5 pinnularia interrupta, - - . - 



6 Stauroneis Phcenicenteron, - 



7 Grammatophora Marina, - - - 



8 Pleurosigma Balticum, - - . 



9 Pleurosigma Acuminatum, 



10 Nitzschia Amphioxys, - - - . 



11 Pleurosigma Angulatum, - - - 



12 Grammatophora Oceanica (G. subtilis 



si'ma, J. W. Bailey), - - . . 



13 SuRiRELLA Gemma, - . . . 



14 Nitzschia Sigmoidea, - - . . 



15 Pleurosigma Fasciola, ... 



16 Surirella Gemma, - - - - . 



17 Cymatopleura Elliptica, - - - 



18 Navicula Crassinervis (^Frustulia Sax 



onica, L. Rabenhorst), 



19 Nitzschia Sigma Var., - . . 



20 Amphipleura Pellucida, 



— EupoDiscus Argus, . - - 



The first column gives the number 

 of the diatom on the test-plate, the 

 second the name of the diatom, the 

 third the person who named it, the 

 fourth the direction of the striae, and 

 the fifth the number of lines in the 

 thousandth of an inch, as determined 

 by Professor E. W. Morley, whose ex- 

 perience gives authority to the results. 



C. G. Ehrenberg. 

 C. G. Ehrenberg, 

 C. G. Ehrenberg, 

 C. G. Ehrenberg, 

 C. G. Ehrenberg, 

 W. Smith, - 

 C. G. Ehrenberg, 

 W. Smith, 

 W. Smith, - 

 F. T. Ktitzing, 

 A. Grunow, 

 W. Smith, 

 W. Smith, - 



C. G. Ehrenberg, 

 C. G. Ehrenberg, 

 W. Smith, 

 W. Smith, - 

 C. G. Ehrenberg, 

 A. DeBrebisson, 



A. DeBrebisson, 

 W. Smith, - 

 - F. T. Kiitzing, 

 C. G. Ehrenberg. 



Hexagonal, 

 Transverse, 

 Transverse, 

 Transverse, 

 Transverse, 

 Transverse, 

 Transverse, 

 Transverse, 



• Transverse, 



Transverse, 

 Diagonal, 



Transverse, 



Transverse, 



Transverse, 



Transverse, 



Longitudinal, 



Transverse, 



Transverse, 

 Transverse, 

 Transverse, 



3-7 

 13.0 

 16.0 



24-5 

 26.0 



34-5 

 38.4 

 33-1 

 46.4 



49.2 

 47.0 



61.6 



53-5 

 62.0 

 58.0 

 67.0 

 63.0 



86.2 

 90.0 

 95-2 



Staining Tissues in Microscopy.— 

 YI. 



BY PROF. HANS GIERKE. 

 \^Continited from p. 2/6.'} 

 129. Ehrlich. Borner's d'tsch. med. 

 Wochenschr., 1882, No. 19. 

 The modification of Koch's meth- 

 od, introduced by Ehrlich and now 

 everywhere adopted, consists in sub- 

 stituting for potash, anilin, which is 

 a yellowish, oily fluid, that, diluted 

 with water, dissolves the dye much 

 better than the dilute alkali. Strong 

 mineral acids are used for bleaching. 

 He thinks the bacillus of tubercle is 

 inclosed in a sac, which is only 

 penetrated by alkalies, not by acids 

 or neutral solutions. If the dye is 

 alkaline it will be bleached by acids. 

 These dissolve the dye and remove 

 it from the other constituents of the 

 preparation, but cannot enter the in- 

 ner part of the tubercular bacillus, 



hence it remains colored. The recipe 

 is as follows : — Sprinkle a little anilin 

 in water to make a 3 per cent, solu- 

 tion, filter. Add a strong alcoholic, 

 basic anilin color, as gentian violet 

 or fuchsin, till a precipitate forms. 

 Filter, and the stain is ready. Let 

 the material soak for 24 hours in the 

 cold, or one hour in a warm chamber 

 at 50°. The sections are then trans- 

 ferred to 30 per cent, hydrochloric 

 acid till they appear bleached, which 

 only takes 1-3 minutes ; they are 

 then dehydrated in absolute alcohol 

 and cleared in oil of cloves. The 

 tissues may be subsequently stained 

 with other colors. 



130. Baumgartcn. Ueber ein beq- 

 uemes Verfahren, Tuberkel- 

 bacillen in Sputennachzuweis- 

 en. Ccntralbl. f. d. med. 

 Wiss., 1882, No. 25. 

 A modification of the two preced- 



