58 MAINE AGRICULTURAL EXPERIMENT STATION. I9IO. 



of these species will grow in an alkaline medium. When grown 

 in a medium containing sugar, Endomyces Magnusii does not 

 cause as great an increase in acidity as is brought about by the 

 Endomyces from apple. 



Cytological. 



Considerable work has been done in an attempt to study the 

 Endomyces from apple from a cytological standpoint. The fact 

 that it grows readily and produces asci and spores in abundance 

 on a large number of culture media would seem to make it a 

 favorable object for study, but the difficulties of securing good 

 fixation and the sm.all size of the nuclei have made it impossible 

 to determine many of the important points which it is desirable 

 to have cleared up in regard to the behavior of the nucleus and 

 the method of spore formation in this group of fungi. A few 

 things have been determined, however, which are of some in- 

 terest. 



Material for study was taken from actively growing cultures 

 on prune agar and in prune decoction and also from apples 

 which had been inoculated with the fungus and which were 

 decaying. Material from such decaying apples showed large 

 numbers of spore sacs and this seemed to be a very favorable 

 place for the development of the ascospores. A number of fixing 

 fluids were tried including Flemming's of different strengths, 

 chrom-acetic acid, picric acid, picro-formol, and absolute alco- 

 liol. Some of the material from agar cultures and from decay- 

 ing apples was imbedded in paraffin and sections were cut 5 and 

 8 microns in thickness. Sections were stained with Flemming's 

 triple stain and with iron haemotoxylin. Some good prepara- 

 tions for determining certain points were prepared by teasing 

 out material which had been fixed, and staining on the slide with 

 iron haemotoxylin. The method followed in doing this was to 

 prepare the slide with egg albumen fixative just as for fastening- 

 sections to- slide, then material which had been run down from 

 higher grades of alcohol to 30 per cent alcohol or water, was 

 teased out on the slide and the alcohol or water was allowed to 

 evaporate, care being taken that the slide did not become entirely 

 dry. When almost dr}^ the slide was placed in absolute alcohol 

 which coagulated the albumen and fastened the material to the 

 slide. Such material Avas stained with iron haemotoxylin. 

 Some of the best preparations were from material .grown in 



