PANAEOLUS CAMPANULATUS 279 



earlier generations, we have a right to conclude that the eighteen 

 basidia represent more than three generations. The number is 

 probably about five. 



The successive generations of basidia have been enumerated in 

 their entirety. We must now turn our attention to those other 

 elements of the hymenium which are called paraphyses. I have 

 studied paraphyses in various Coprini, in Bolbitius, Psathyrella 

 disseminata, Lepiota cepaestipes, Stropharia semiglobata, etc., and 

 my conception of their nature may be stated as follows. Para- 

 physes are hymenial cells sui generis, which (1) numerically con- 

 stitute a large proportion often 50 per cent, or more of the total 

 number of hymenial elements, (2) usually differ more or less in shape 

 from the cystidia and basidia, (3) as they grow older and larger, 

 become progressively poorer in protoplasmic contents, and (4) never 

 produce either sterigmata or spores, so that they remain sterile 

 from their first origin to their death. I regard paraphyses as 

 destined from their first origin to remain sterile. I see no reason to 

 believe that, after spore-discharge has begun, any paraphysis ever 

 turns into a basidium or, vice versa, that any young basidium ever 

 turns into a paraphysis. The question now arises whether or not 

 paraphyses occur in the hymenium of Panaeolus campanulatus. 



If one cuts a transverse section through the hymenium of a gill 

 that has been shedding spores only for a short time, say 24 hours, and 

 if one studies the section with the microscope, it is not very easy to 

 decide the question of the presence or absence of paraphyses. True 

 it is that one can see here and there some small hymenial elements 

 pushing up, as it were, between the bases of undoubted basidia and 

 developing one or more vacuoles in their interior, but other cells 

 which are similar in shape, not much larger, provided with but 

 slightly more protoplasm, and which presumably are young basidia, 

 occur along with them. One feels insecure when one pronounces 

 that this small cell is a paraphysis but this other, differing from it 

 so little in shape, size, and contents, is a very young basidium. 

 The difficulties in distinguishing paraphyses from basidia are, 

 however, not insurmountable, provided that they are approached 

 in a suitable manner. 



In devising a new method for solving the problem of the presence 



