406 



The results indicate the acid to be stronger in its effect than the cor- 

 responding salt, though PeniciUium is a plant which grows luxuriantly on 

 acid fruits. The sodium sulphite bleached the solutions, \% being a pale 

 straw color. The copper sulphate solutions were also changed in color, 

 the \% solution was a decided green. 



In all cases microscopic examination was made of material from the 

 flask cultures, and indicated more conclusively than the gross appearance 

 the effect on the development. Submerged colonies have been used for 

 the reports in the table, as they are more uniform. The surface colonies 

 have the characteristics of the submerged in their earlier growth, .but as 

 development proceeds and the hyphre grow away from the medium, the 

 characteristics may change, sometimes more nearly approaching the nor- 

 mal, or they may develop characters more pronounced than the submerged. 

 In a few instances, only submerged colonies, and in the raw cranberry 

 and cinnamon solutions only surface colonies, developed. In making meas- 

 urements the germinated spores were used, and only the average sizes ; 

 the extreme in size was avoided, as not giving a fair estimate of the effect 

 of the preservative. Where only one measurement is given, it indicates 

 that the spores were fairly uniform ; where two measurements are given, 

 the spores showed such strong -variation that an average was taken of the 

 smaller and also of the larger instead of taking the average of the two 

 sets. The hypha? were measured but varied so much that it was thought 

 a better estimate could be obtained from the photographs. 



Microscopic Appearance of Penicillium Grown in Preservative 



Solutions. 



Preservative. 



Size of 

 Germinated 

 Conidia in //. 



Characteristics of Development. 





8.5 



7.6 

 7.6 





Salt, 5% 



pering tips, homogeneous protoplasm, many large round 

 vacuoles. 



Sugar, 50% . . 



blunt tips. 



Hyphae shrunken, distorted, homogeneous protoplasm, vacuoles 

 show as pink spots, giving a beaded appearance. 





