89 



292. Model of Spirillum volutans, Colin. ; enlarged 

 15,000 diameters. 



E. 32/. 1884. Made by E. Brendel, Berlin. 



Showing a thread consisting of three segments with two 

 flagella. 



293. Model of Spirochcete Obermeieri, Colin., the 

 gerin of relapsing fever ; magnified 10,000 diameters. 



E. 32^. 1884. Made by E. Brendel, Berlin. 



Two distinct forms are shown, mounted on the same stand. 



294. Set of six models illustrating the morphology 

 and life history of Saccharomyces cerevisice, Meyen, the 

 yeast plant ; highly magnified. 



E. 31a to e. 1884. Made by E. Brendel, Berlin. 



1, 2. Yeast of the lower fermentation. The yeast cells are 

 isolated or have only one small bud growing from them. 



3. Yeast of the higher fermentation. The cells are connected 

 with strings. 



4. Daughter-cells in groups of four within the mother-cell. 



5. Free daughter-cells (spores) hefore germination. 



6. Spores germinating. 



295. Enlarged model of the Sporogonium of a moss 

 (Polytrichum commune). 



E. 135. 1874. Made by the late Dr. Auzoux, Paris. 



The hairy calyptra, the operculum, and the epiphragm are all 

 movable, and the walls of the theca can be separated to show 

 the cavity with its contained spores. 



296. Enlarged model of a grain of wheat (Triticum 

 cestivum, L.). 



E. 134. 1874. Made by the late Dr. Auzoux, Paris. 



The model can be bisected to exhibit the internal structure 

 the embryo, which is in sections, can be taken out, and replaced 

 by a second model of the embryo showing its appearance in a 

 more advanced stage of growth. 



297. Enlarged model of the spikelet of wheat (Tri- 



ticum vulgar e^ L.). 



Made by Montaudon (late Dr. Auzoux), Paris 

 E. 9. 1891. 



The glumes and two complete florets can be removed, showing 

 the nectaries, stamens, and pistil. The whole spikelet is first to 

 be detached from the stem. 



