392 



chambers had a few drops of the culture medium placed iu the bottom, 

 so as to keep the vapor tensiou unaltered. 



The cultures were examined at regular intervals, as indicated in the 

 tables, those in the flasks having specimens taken for examination with 

 the miscroseope. The points noted were the swelling of the spores pre- 

 ceding germination, the length of hypho?. and the earliest appearance of 

 conidiophores. for the cultures in the moist chambers. For all other cul- 

 tures a hand lens was used to determine the first appearance of germina- 

 tion. The appearance of the conidia was shown by the blue color, and the 

 maturing by the change in color from the blue to green, and then to olive. 

 The volume of mycelium and conidia was noted to determine the extent 

 of development. 



Penictllium Grown in Tomato Bouillon 500 cc. 70° F. 



Per Cent 

 Sod. Benz. 



Time to 

 Germ. 

 Hours. 



Development. 



1-12 



1-10 

 1-5 



1-2 



24 



48 



48 

 120 



Spores germinated. 



48 hours — surface covered. 



72 hours — spores developed, surface blue. Hyphae uniform in outline, protoplasm 



homogeneous, many vacuoles. 

 120 hours — fully matured. 



Thin ring at edge, small colonies submerged. 



120 hours — surface covered, blue. Hyphse, uneven outlines, protoplasm granular, 



walls broken easily. 

 240 hours — fully matured. 



Slightly less developed than in the preceding, otherwise alike. 

 240 hours — fully matured. 



Thin interrupted ring at edge. 



168 hours — spores swollen, irregular in outline, filled with coarsely granular pro- 

 toplasm, walls broken by cover glass. 

 336 hours — surface dotted with colonies, showing blue spots. 

 348 hours — fully matured. 





The effect of the sodium benzoate on the development is shown in a 

 retarded and abnormal development, these being accentuated as the amount 

 of the salt was increased, to a point where no development occurred. 



