82 PROTECTION OF PLANTS — 1922-23 



be identical with the original cultures. In one instance, however, two different 

 types of colonies appeared on the poured plates. Separate transfers were made 

 and organisms K and L were made. 



By means of this method seventeen pure cultures were obtained. As the 

 experimental work progressed it became evident that a number of them were 

 duplicates. These were accordingly discarded and the work completed with 

 five isolations secured in the manner described and the additional three obtained 

 from Maine and Cornell. 



During the course of the investigations, stock cultures of the eight organ- 

 isms were niaintained, transfers being made approximately every three weeks. 

 From these stock cultures subcultures were made on the various media used in 

 the different experiments. Frequent microscopic examinations of these stock 

 cultures were made as check on their purity. In no cases were any contamina- 

 tions detected. 



Classificaton of the organism studied. 



The genus, in order to facilitate its study, has been divided into a number 

 of sections by Wollenweber (16: 1913) and by Sherbakoff (12: 1915). The writer 

 has grouped the organisms here studied according to these sections. 



Section Elegans. 



1. F. orthoceras A. & W. Wollenweber (16: 1923) gives the following 

 diagnosis of this species: sporodochia and a reduced pionnotes present, inmasses 

 salmon coloured, the conidia of both being 3-septate, up to 100%, 25-45 x 3.25- 

 4.5 u, 4-septate, up to 25%, 5-septate up to 10%, where they are 40-50 x 3.75- 

 4.75 u in size; sclerotia blue on steamed potatoes; shght lilac odour on steamed 

 rice; common soil organism and a vascular parasite on many hosts, as, Solanum, 

 Vigna, F*isum, Ipomoea, etc. 



No. G in the series here studied agrees closely with this description. The 

 lilac odour is not pronounced, however, and the colour is more of a cream shade 

 than salmon. The 3-septate spores are 21.0-45.5 x 2.6-4.4 u, 4-septate, 35.0-42.0 

 x 3.5-5. 2 u. Only a single 5-septate spore was observed and it measured 45.5 

 X 4.4 u. 



2. No. F differs in some respects but as a whole coincides fairly closely. 

 It is a more vigorous organism in amount and rate of growth and spore pro- 

 duction than G, but when colour is produced in the medium (wine-red on rice) 

 the latter organism gives a more intensive hue. The 3-septate spores measure 

 22.5-52.5 X 2.6-6.1 u, 4-septate, 35.0-49.0 x 3.5-6.1 u, 5-septate, 38.5-52.5 x 



