STUDIES OF GLOMEEELLA PKOM DIFFEKENT HOSTS. 33 



dark-brown color and a few acervuli were found. Perithecia were 

 also present, especially along the midrib. Some were single and 

 others aggregated in groups. Mature asci were seen. The perithecia 

 and ascospores were apparently identical with those obtained from 

 other species of Ficus and could not be distinguished from the forms 

 of Glomerella from various other hosts. Asci and ascospores are 

 shown on Plate II, figures 19 and 19a. 



CULTURES. 



On December 12 plates were poured, using conidia from leaves in 

 moist chamber. The growth was of the usual character and pro- 

 duced a few acervuli, but no perithecia ever appeared. 



On February 3 subcultures from these plates were made in flasks 

 of corn meal. The course of development was as usual, and on Feb- 

 ruary 25 acervuli with pinkish masses of conidia were present. 

 Peritheciumlike bodies were also found on the sides of the flask, but 

 no asci or ascospores could be discovered. 



On April 28 plates of different dilutions were poured, using conidia 

 from the cultures just described. On May 4 the plate most thinly 

 sown showed a considerable number of acervuli. The next plate, 

 in which more conidia were used, showed very few acervuli. The 

 third plate, in which a still larger quantity of spores was used, showed 

 many scattered conidia but no acervuli. In the cultures where 

 numerous spores were sown, acervuli were much fewer than in those 

 where the spores were more scattered. This behavior may perhaps 

 have some direct relation to the greater quantity of nutriment avail- 

 able in the case of the thinner sowings than in the other. No perithecia 

 were ever found in these cultures, although perithecia were present 

 on the leaves from which the cultures were made. This may possibly 

 have been due to the fact that both fertile and sterile strains were 

 present on the leaves and the conidia used happened to be taken from 

 acervuli belonging to a nonperithecium-producing strain. 



Conidia from leaves in moist chamber varied from 15 to 20 by 

 5 to 6 fi, averaging slightly thicker than in most of the other forms. 

 Conidia in plates varied from 13.5 to 16.5 by 5 to 6 <i. Ascospores 

 ranged from 15 to 22 by 4.5 to 6 fi. No paraphyses were seen. 



GINKGO BILOBA L. 



Glomerella cingulata (Stonem.) S. and v. S. 



Fallen leaves of this plant taken from the grounds of the Depart- 

 ment of Agriculture were washed as usual and placed in a sterile 

 moist chamber. In a short time acervuli of Gloeosporium formed on 

 the leaves. 



On November 13 potato-plug cultures were made by transferring 

 conidia from the acervuli on the leaves in the moist chamber. On 

 46023°— Bui. 252—13 3 



