Fungi 197 



Peziza. The Pezizas and related forms are fleshy, and present 

 but little difficult}^ in fixing, cutting, or staining. They are abundant 

 in moist places, on decaying wood, or on the ground. The apothecia 

 have the form of little cups, which are sometimes black and some- 

 times flesh-colored, but often orange, red, or green. 



For general morphological work it is better to tease out fresh 

 or preserved material. Such views as that shown in Fig. 52 are easily 

 obtained in this way. For permanent preparations showing such 

 views, it is better to stain in bulk in alum carmine or in Delafield's 

 haematoxylin, and then tease out the asci in glycerin or balsam. 

 Sections showing the entire ascus should be 10 to 15 ju in thickness. 



For the free nuclear division in the ascus, and also for the develop- 

 ment of the ascospores, Flemming's weaker solution, followed by 

 the safranin, gentian- violet, orange combination has given the best 

 results. Cyanin and erythrosin are also to be recommended. The 

 latter combination stains better when the fixing contains no osmic 

 acid. Sections should be 3 ju in thickness; if thicker than 5 ju, they 

 are likely to prove unsatisfactory for any cytological study. 



Eurotium. Eurotium with its conidial stage, Aspergillus, is a 

 very common mold found on bread, cheese, decayed and preserved 

 fruit, etc. In the conidial stage it is green and in the ascosporic 

 stage, yellow, reddish yellow, or reddish brown. Aspergillus is 

 almost sure to appear upon bread which is kept moderately moist, 

 because the conidia are usually abundant in the atmosphere. If 

 the bread be wet with a 10 per cent solution of cane-sugar or with 

 grape juice, this stage appears sooner and in greater abundance. 

 A temperature of 22 to 30 C. is also a favorable condition. 



The perithecial stage is not found so frequently, but can generally 

 be secured by examining moldy preserves. However, if one has the 

 mycelium or spores, the sexual stage can be induced. Soak a piece 

 of bread in a 20 per cent solution of grape-sugar in grape juice; upon 

 this sow the spores and keep at a temperature of about 28 C. After 

 4 or 5 days, begin to examine. A 40 per cent solution of cane-sugar 

 in the juice of prunes is also a good nutrient solution. 



For class use or for permanent preparations it is best to select 

 rather young material which shows various stages in development, 



