22 PAKASITES BELONGING TO THE GENUS GLOMERELLA. 



leaves taken from greenhouse plants have frequently been treated 

 with corrosive sublimate and placed in sterile moist chambers. Such 

 leaves have almost invariably produced an abundant growth of acer- 

 vuli, which is frequently followed by the development of perithecia 

 with typical asci and ascospores. The time required for the develop- 

 ment of perithecia is usually two to four weeks. 



Poured plates made with conidia from leaves kept in moist chamber 

 produced a growth very similar to that obtained from other hosts. 

 The number, size, and distribution of the acervuli formed vary con- 

 siderably. Setae were not usually present in these plates. Several 

 series of plates produced only conidia. Two showed a few perithe- 

 ciumlike bodies, but no asci were found. Different tubes showed 

 considerable difference in the appearance of the growth. In some it 

 was light colored and scanty; in others, abundant and dark. 



Cultures were made from conidia taken from an orange leaf 

 received from Houston, Tex., March 10, which was treated as usual 

 and kept in sterile moist chamber until March 29. Transfers of 

 single germinating conidia to corn-meal agar tubes were made. The 

 growth was of a smoky-brown color, resembling that of cultures, from 

 pomelo hereafter described. A few large acervuli were formed, but 

 no perithecia, though perithecia were produced on leaves in moist 

 chamber. Later, setae were found in abundance. 



CITRUS DECUMANA (POMELO). 



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

 Colletotrichum gloeosporioides Penz. 



DEVELOPMENT ON LEAVES IN MOIST CHAMBER. 



On March 28 apparently healthy leaves of the pomelo were taken 

 from greenhouse plants and placed in sterile moist chambers. They 

 soon became spotted and acervuli appeared. These were soon followed 

 on darker areas of the discolored leaf by perithecia, which showed 

 mature asci on June 20. Setse were not found in the acervuli on 

 these specimens. 



On April 30 two apparently healthy leaves were taken from imme- 

 diately below a cluster of young fruit ; also an older leaf, from whose 

 axil a fruiting shoot was produced. These leaves were treated as usual 

 and placed in sterile moist chambers. On May 7 acervuli were found 

 regularly scattered over the surface of the older leaf, but there were none 

 on the two young leaves. On May 13 the base of one of the young 

 leaves showed slight discoloration running up the midrib three-fourths 

 of an inch. On May 15 both young leaves were discolored along the 

 midrib. Acervuli developed abundantly on these young leaves later. 

 On June 9 perithecia and asci were found on the old leaf. This experi- 

 ment, like those with the orange, apparently showed the presence of 



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