NOTES ON SCOTCH PLANTS. 89 



formation of the terminal obovate cells borne by the specialized 

 septate portions of the hymenial hyphre, then in P. indica the wall 

 of the obovate terminal cell is recognised as au ascus, its protoplasm 

 resolves itself into a spore surrounded by its own cell-wall, which 

 in course of time escapes from the mother-cell or ascus, leaving 

 the latter permanently attached in a shrivelled condition to the 

 mother-cell, from which it originated. In P. Emerici the obovate 

 bodies become directly transformed into spores, the original cell- 

 wall adhering to, and forming a somewhat loose investment on the 

 inner and thicker true wall of the spore ; as the latter increases in 

 size, the outer wall — homologous with the ascus in P. indica — 

 becomes closely adnate to the inner, coloured wall, but can be 

 readily separated by the application of sulphuric acid. When I first 

 saw the spores of P. Emerici, each with its very evident hilum or 

 point of attachment, I searched further for the basidia, as figured 

 by Fischer in P. carcinomalis, each basidium bearing four sessile 

 spores at its apex ; but I am convinced from repeated examinations 

 that in P. Emerici the spores, which are the homologues of spores 

 and asci combined in P. indica, fall away directly from the septate 

 mycelium. Now it is clear that the spores of P. Emerici cannot be 

 called ascospores, because they are not produced in asci or mother- 

 cells, from which they eventually escape, and, if not ascospores, 

 they must in the broader sense be basidiospores, and, if so, the 

 sparsely septate portion of mycelium from which they originate 

 must be a basidium. It must not be supposed that the transition 

 from ascospores to basidiospores is abrupt ; in P. Emerici mixed 

 with basidiospores, characterized by the well-marked hilum, may 

 occasionally be seen perfectly smooth spores without any trace of a 

 hilum ; such spores are technically ascospores, having escaped from 

 the mother-cell, contrary to the rule, and it is not rare to find 

 spores with the outermost portion corresponding to the ascus in P. 

 indica, split and partly removed (fig. 26) ; in fact, there is in 

 P. Emerici every transition of spore-origin between what has been 

 spoken of as ascosporous and basidiosporous respectively ; further- 

 more, I have reason to believe that in every species of Podaxis there 

 is a sprinkling of spores produced as basidiospores, that is, spores 

 falling away with the wall of the obovate cell as a permanent 

 external investment, instead of escaping from this wall, which then 

 is considered as an ascus, as is most usual in all species, except P. 

 Emerici, where the reverse holds good regardhig the proportions of 

 the two modes of spore-formation. 



(To be continued.) 



NOTES ON SCOTCH PLANTS. 



By G. Claridge Druce, M.A., F.L.S. 



The following notes were made on a visit to Strath Tay in 1888, 

 and to Easterness, Banff, Elgin, and Boss-shire in 1889. The first 

 visit was marred by wet weather and a backward season, which 



