. Annual report of the New York State College of Agriculture at Cornell University and the Agricultural Experiment Station. New York State College of Agriculture; Cornell University. Agricultural Experiment Station; Agriculture -- New York (State). i68 Bulletin 395 condition, surrounded by the remainder of the ascocarp, give the appear- ance of one of the true discomycetes. This, however, is brought about by the persistency of the outer cells of the shield-like layer which covers the immature ascocarp. In the presence of sufficient moisture the exposed asci elongate to approximately three time
. Annual report of the New York State College of Agriculture at Cornell University and the Agricultural Experiment Station. New York State College of Agriculture; Cornell University. Agricultural Experiment Station; Agriculture -- New York (State). i68 Bulletin 395 condition, surrounded by the remainder of the ascocarp, give the appear- ance of one of the true discomycetes. This, however, is brought about by the persistency of the outer cells of the shield-like layer which covers the immature ascocarp. In the presence of sufficient moisture the exposed asci elongate to approximately three times their usual length. This process is very rapid and may be observed under a microscope when a fragment of tissue containing asci is placed in a drop of water. The lower part of the ascus remains fastened in the cavity in which it was borne, giving a conical shape to the body which raises itself above the surrounding tissue. The spores gather at the tip of the ascus and from there are ejected into the air. They have been caught at a distance of one centimeter above the lesions. Even in a single asco- carp all the asci are never of the same age, and the ascocarps on the same cane seem to vary in this respect. In 1915 mature ascospores were first ob- served about the first of June, while other asco- spores were not mature until later in the summer. The ascospores, like the conidia, have walls which are very gelatinous and stick>^ and great difficulty was experienced in tr^nng to pick up single spores by means of a glass tube, as described by Barber.^ The spores adhere especially to the glass slides, and it was impossible to get them into the bore of the tube. Single asci, however, could be separated in this manner. When placed in tap, rain, or distilled water, or on nutrient agar, the mature ascospores germinate very readily. They swell somewhat, and within less than two hours a short sterigma is produced from one or each of the cells. A sprout conidium is formed, which is fro
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