784 Journal of Agricultural Research voi.xx.No. 10 



(7) When the enzym is in suspension some of it is removed by filtering 

 through Whatman chemically prepared filter paper. 



(8) The temperature at which the fungus is grown has a marked in- 

 fluence on the production of intercellular amylase. With an equal 

 weight of enzym powder it was found that mycelium grown at 9 C. 

 hydrolyzed about four times as much starch in the same length of time 

 as mycelium grown at 40 . The enzym powder of mycelium grown at 29 

 was intermediate between the other two. At these three temperatures 

 the best growth of the fungus was made at 29 and the poorest at 9 . 



(9) The results of these investigations show that there is a " quantita- 

 tive regulation" of the enzym. The hydrolyzing power of the mycelium 

 grown on Czapek's modified nutrient solution was much greater when 

 starch alone was used as a source of carbon than when glucose alone or 

 in combination with starch was employed. On the other hand, if grown 

 on sweet potato bouillon, which contains both starch and sugars, a unit 

 weight of the mycelium will hydrolyze more starch than when grown on 

 any of the other combinations. The vigor of growth of the fungus was 

 correlated with the hydrolytic power of the enzym powder. The results 

 seem to indicate that it is not so much the source of the carbohydrate 

 which influences the quantitative production of the enzym as it is the 

 influence which it has on the growth of the fungus on which the secretion 

 of the enzym depends. 



(10) The enzym powder of young mycelium just beginning to fruit 

 was more active than the enzym from old mycelium. 



LITERATURE CITED 



(1) Armstrong, Henry E., and Armstrong, E. Frankland. 



1907. STUDIES ON ENZYME ACTION. X. — THE NATURE OP ENZYMES. In 



Proc. Roy. Soc. [London] s. B, v. 79, no. 533, p. 360-365. 



(2) Bayliss, W. M. 



1911. THE nature OP Enzyme action. Ed. 2, 137 p., 7 fig. London, New 

 York [etc.]. List of literature referred to, p. 121-132. 



(3) Brown, Adrian J. ■ % 



1904. LABORATORY STUDIES FOR BREWING STUDENTS. I93 p., 36 fig. London, 



New York [etc.]. 



(4) Brown, Horace T., and Glendinning, T. A. 



1902. THE VELOCITY OF HYDROLYSIS OF STARCH BY DIASTASE, WITH SOME RE 



marks on enzyme action. In Jour. Chem Soc. [London], Trans, 

 v. 81, pt. 1, p. 388-400. 



(5) and Heron, John. 



1879. CONTRIBUTIONS TO THE HISTORY OF STARCH AND ITS TRANSFORMATIONS. 



In Jour. Chem. Soc [London], v. 35, Trans., p. 596-654, 12 fold. tab. 

 (6) and Morris, G. H. 



1890. RESEARCHES ON THE GERMINATION OF SOME OF THE GRAMINEAE. In 



Jour. Chem. Soc. [London], v. 57, Trans., p. 458-528, 2 pi. 

 (7) Brunton, T. Lauder, and MacFadyen, A. 



1890. the ferment-action of bacteria. In Proc Roy. Soc. [London], v. 

 46, 1889, p. 542-553. 



