74 MB. E. J. HAETET GIBSON ON THE STBUCTTJRE 



found to be bounded by a delicate cuticle pierced at intervals for 

 the exit of the processes already mentioned. Immediately within 

 is the clear border formed by the swollen coalesced outer cell- 

 walls of the peripheral cells* Then follows the rind of cortical 

 coloured cells, rather smaller and more numerous than, but 

 similar in arrangement to, those of the ordinary branch. This 

 layer passes gradually into the central weft of hyphae conti- 

 nuous with those of the branch from which the cystocarp springs. 

 In the inner portion of the rind and outer part of the medullary 

 weft there arise from the cell-threads very numerous branchlets 

 consisting of generally two cells, one short and rounded, the other, 

 the trichogyne, broad at the base but tapering into a fine filament 

 which pierces the rind and cuticle, and appears on the surface as a 

 delicate colourless, or almost colourless, hair. Not infrequently this 

 trichophoric apparatus consists of three cells — two basal tricho- 

 phoric cells and the trichogyne (PI. XIII. figs. 7, 8). Tig. 9, 

 PI. XIV., shows a small portion of the surface of a young cysto- 

 carpic ramulus highly magnified. To two of the trichogynia 

 pollinoids are attached, while two others have not yet pierced the 

 cuticle. The majority of the trichogynia in an older cystocarp 

 may be seen to have pollinoids attached to them. The medulla 

 of a young cystocarp consists of a weft or reticulum of almost 

 colourless cells, the central row standing out rather prominently. 

 Round the central row and connected with it are half a dozen or 

 more rows of cells, branches from which form the beginning of the 

 reticulum of smaller cells which gradually merges into the inner 

 rind. Pig. 10 shows such a section (rather more than half the 

 section is represented) taken in the exact longitudinal axis of the 

 cystocarp, in which the features just described are seen. (The 

 figure has been somewhat simplified by omission of all cells which 

 do not come exactly into the plane of the section.) 



After, and sometimes (so far as I can make out) before, 

 fertilization of the trichogynia has taken place there appear a 

 few small subsidiary cells round the trichophoric cell or cells. 

 These subsidiary cells I imagined at first were young carpo- 

 Bpores, and what I have termed trichophoric cells, carpogonia ; 

 and I interpreted the mass of spores found in an adult ramulus 

 as composed of bundles of such derived from many carpogonia 

 developed nearer to the central medulla. Prof. Sehmitz, how- 

 ever, pointed out to me that I had misinterpreted these pheno- 

 mena ; and I am convinced now, after examining sections of very 



