328 THAXTER. 



criminately throughout the compact mass, which becomes very hard 

 on drying. On the surface of the spore-mass, which is subspherical, 

 slightly umbilicate, and rather firmly attached to the substratum 

 which it may partly envelope (Fig. 79), the hyphae gather in rather 

 regularly disposed, compact, attenuated, radiate, discrete bundles. 

 Figure 80, 60-100 n in length and 12-30 /x at the base, while the apex 

 may be less than 2 jx. The hyphal elements which form these bundles 

 are so firmly and closely coherent that the individual filaments which 

 compose them can only be distinguished with a high magnification or 

 by crushing them apart. They form the conspicuous superficial 

 tomentum which, although it may be less evident in older specimens, 

 is very striking in younger individuals (Fig. 79). 



Although the peculiarities of the hyphae and spores above referred 

 to, might not be regarded as very convincing evidence for the separa- 

 tion of this species from Endogone, I have preferred to keep it dis- 

 tinct provisionally. The indiscriminate distribution of its spores in a 

 solid mass would certainly forbid its inclusion in Sclerocystis, as repre- 

 sented by S. coremioidcs and S. Dussii, in both of which they are dis- 

 posed " en une seule zone radiale," about a central columella. 



The rather close resemblance between the general appearance of 

 this species and that of Endogone pisiformis, above alluded to, might 

 suggest that they were possibly stages in the cycle of a single fungus; 

 S. pubescens representing the chlamydosporic condition of the zygo- 

 sporic type. The character of the hyphae appears to be so different 

 in the two cases, however, that such a connection seems very improba- 

 ble, and although their habitats are similar, I have never seen them 

 closely associated in Nature. 



SCLEROCYSTIS B. & Br. 



Berkeley & Broome (1873), p. 137. 



Xenomyces, Cesati (1879), p. 26. 

 Ackermannia, Patouillard, (1902), p. 180. 



Type Species 



Sclerocystis coremioides B. & Br. 



Berkeley & Broome (1873), p. 137, Plate X, fig. 56. 



Xenomyces ochraceus Cesati (1879), p. 26. 



Sphaerocreas Javanicum von Hohnel (1908), p. 30, fig. 1. 



