282 RESEARCHES ON FUNGI 



What is the function of the paraphyses ? In some Hymeno- 

 mycetes, like the Coprini, Lepiota cepaestipes, and Psathyrella dis- 

 seminata, in which the organisation of the hymenium (to be discussed 

 later) differs from that of the Panaeolus Sub-type, the paraphyses 

 are absolutely necessary to keep the spore-bearing basidia apart. 

 In these species the paraphyses, which are of large size, are not 

 merely in contact with one another but adhere together so as to 

 form a continuous and firm tissue through the gaps of which the 

 basidia protrude themselves at intervals. No doubt, under these 

 conditions, the paraphyses, in addition to fulfilling their chief 

 function of separating the basidia and therefore of preventing their 

 mutual interference, also serve to support the basidia so as to 

 preserve them in their upright positions. Further, they probably 

 help to supply the basidia with water which is required to compen- 

 sate for losses sustained in transpiration from the spores, etc. In 

 Panaeolus campanulatus, however, the paraphyses have no very 

 definite order and are not closely adherent (Fig. 94, F, p. 276 ; 

 Fig. 95, B, p. 281), so that one often finds two basidia in contact 

 with one another (Fig. 94, A ; Fig. 95, A). What, therefore, can 

 be said for the function of the paraphyses in this species ? 



Owing to the fact that the basidia in Panaeolus campanulatus 

 come to maturity in a succession of generations, paraphyses are 

 not necessary as space-making elements : any two spore-bearing 

 basidia can be separated by immature or exhausted basidia. I do 

 not think, therefore, that the paraphyses here have the same chief 

 function as they have in the Coprini. On the other hand, the 

 paraphyses are probably useful in supporting the spore-bearing 

 basidia in upright positions, especially toward the end of spore- 

 discharge when most of the basidia are dead ; and, doubtless, they 

 also conduct water into the basidia which, when protuberant and 

 bearing four spores, must often transpire considerable quantities 

 of it. If there were no paraphyses in the hymenium, many or most 

 of the basidia w r ould stand isolated on their narrow bases, and they 

 would all expose a much larger superficial wall-area. Surely, under 

 these conditions, the basidia would have greater difficulty in taking 

 up positions perpendicular to the gill -surf ace and also in obtain- 

 ing the increased amount of water which would be required for 



