JOHNSTON. ON CAULOGLOSSUM TRANSVERSARIUM. 63 



The youngest stages examined in which any differentiation of impor- 

 tance was observed is represented in fig. 8, in which a distinct layer (x) 

 of interlacing hyphae covers the more compact columella (y). Between 

 the two is a deeply staining region (z) running lengthwise with short 

 folds. This layer may be seen to consist of the tips of hy[)hal branches 

 arranged in a columnar fashion, closely packed, and arising from a looser 

 indefinite region below, which is made up of branching hyphae proceed- 

 ing directly from the columella. This compact, deeply staining layer, 

 which is the initial gleba, has no connection with the peridium lying next 

 to it, but becomes gradually merged at both ends into the hyphae of the 

 columella. The peridium is thus pushed away from the axis of the 

 fruiting body by the growing gleba ; and its further growth, which is 

 relatively inconsiderable, is independent of the structures which it sur- 

 rounds. At the base and the apex of the fruiting body, its connections 

 are a little more evident. At the apex the peridium is indistinctly differ- 

 entiated from the columella, and though the hypliae of both anastomose 

 in this region, this differentiation becomes more marked with further 

 growth; not to the extent, however, of final separation. At the distal 

 end of the stipe the hyphae of the peridium and of the axis are closely 

 intermingled, anastomosing freely, as do also the hyphae of the peridium 

 with those at tlie apex of the columella ; the distinction between the axil 

 and the peripheral layer in each case lies in the fact that the hyphae 

 of the axis constitute a firm coherent mass, while the hyphae of the 

 peridium form a thin flocculent layer. These conditions are repre- 

 sented in fig. 13, which is an enlarged view of a portion of fig. 8 at the 

 apex of the fruiting body. The fact that the initial gleba (z) is not 

 connected with the peridium (x) and arises from the columella (y) is 

 clearly shown in this figure. Here, too, the columnar layer extends 

 gradually into the columella near the apex, at the right in the figure 

 which here includes the ill-defined region of separation between the 

 peridium and the columella. At this point there are thus clearly dis- 

 tinguished in this stage three regions : the peridium, the gleba, and tlie 

 columella ; the gleba consisting as yet merely of folds from the surface 

 of the columella which result from the more rapid multiplication of the 

 elements of the columnar layer in one part, than in another. 



In a somewhat older stage (fig. G), these three regions are seen to 

 liave been still more clearly differentiated from one another. Distinct 

 groups of hyi)hae run out from the columella into the folds tiie surface of 

 which, as previously mentioned, consists of a layer of columnar elenurnts. 

 As the fold pushes farther out and its surface increases, new columnar 



