314 THAXTER. 



maximum diameter observed being 170 ^. In all its characteristics it 

 comes well within the variations of the present species, and there 

 seems to be no reason for maintaining it as a distinct form. 



Endogone jpam-paloniana Baccarini (1903), p. 90, has been examined, 

 through the courtesy of Professor Mattirolo, who has kindly communi- 

 cated a slide of microtome sections from the type of this species. 

 Like most sections of this nature, they are of little use for the pur- 

 poses of specific determination, and it is difficult to decide from them 

 what the distinctive characters, if such exist, really are. Baccarini 

 based the species on the fact that the hyphae between the spores are 

 more copiously developed and compactly woven than in the usual 

 types of E. macrocarpa, in which he conceives the spores, "ampolla," 

 to be simply gregarious, while in E. pampaloniana they form a 

 "cumulo," which he regards as a transitional condition between the 

 loose heap formed in E. macrocarpa, and the more definite sporocarp' 

 of E. lactiflua. The different origin of the spores in E. lactifiua would, 

 however, destroy any significance in such a series. The spores corre- 

 spond in size to those of E. macrocarpa, 120-140 /x, but have much 

 thinner walls, owing perhaps to the immature condition of the speci- 

 men. As has been mentioned above, similar conditions have been 

 found in New England, although the compact " gleba" is characterized 

 by the usual thick-walled spores, and the same is true of Californian 

 material. Until we have much more information concerning the 

 variations of E. macrocarpa it seems desirable to regard E. pampalon- 

 iana as at best no more than a variety of this species. 



Endogone tenebrosa nov. sp. 

 (Fig. 46.) 



Spore-mass spongy, easily disintegrating, blackish. Hyphae loose 

 and friable, 8-40 ix in diameter. Chlamydospores spherical or sub- 

 spherical, 200-270 IX, the largest 260 X 275 jx, brownish yellow, be- 

 coming quite opaque at maturity, the reddish brown wall becoming 

 15-20 IX thick and finally invisible; surrounded by a thin hyaline 

 exospore. 



In Sphagnum. Little Metis, P. Q. E. C. Jeffrey. 



The material of this species is so broken up in the fluid in which it 

 is preserved that it is difficult to determine what was the original form 

 of the irregular spongy masses. The huge spores are readily visible 

 with the naked eye, and become absolutely opaque from the darkening 



