to 
BROOKLYN BOTANIC GARDEN MEMOIRS 
doubtful, however, if true sporulation has ever been observed. In 
dead resting spores the contents often segregate into a number of 
large, rounded or elliptical bodies. In E. reniformis the single spore 
in an “‘ascus’’ is probably the ‘“‘resting spore’’ itself, while in the 
species described as having numerous minute sporidia in an ascus 
(often with an interrogation), the supposed sporidia are probably the 
numerous fat bodies conspicuous in some species. 
ORIGIN AND DEVELOPMENT OF THE ‘‘ RESTING SPORES’’ IN 
ENDOGONE LACTIFLUA BERK. 
Character of the mycelium.—The only important contribution to 
development in the genus Endogone, thus far, was made by Bucholtz 
in 1912, in his study of Endogone lactiflua. This species is subter- 
ranean and occurs in various parts of Europe. The fruit bodies range 
in size from 4 mm. to 2 cm. The material studied by Bucholtz was 
found in a plantation of Abies sibirica in Livland, Russia. The 
mycelium is coenocytic, profusely branched, the hyphae following a 
very sinuous course, but the general direction is radial and toward the 
periphery. It is non-septate, true cross walls being formed only in 
connection with the reproductive organs, though false cross walls are 
occasionally found in the vegetative hyphae. The hyphae vary 
greatly in diameter, in general becoming more slender toward the 
periphery of the fruit body, but irregularities in the form of swellings 
occur. Terminal branches on the interior are often clavate. Sack- 
like enlargements occur from which numerous branches often diverge. 
The walls of the hyphae are thick. The nuclei are minute, very 
numerous, and lie in a parietal layer of cytoplasm. 
The progametes and conjugation.—The progametes are clavate and 
of unequal size. They lie nearly parallel and their walls fuse at the 
lateral point of contact a short distance from the free ends. The 
nuclei in the progametes, lying near the periphery become larger, 
more distinct, and undergo one division. The nuclei now retreat from 
the terminal portion of each progamete and all except one are excluded 
from each gametangium by a cross wall. A few sterile nuclei some- 
times remain in the gametangium but soon degenerate. The origin 
of the selected gamete nucleus in each gametange is not known, but 
it is probably derived from one of the peripheral nuclei in the pro- 
gamete, or one of the daughter nuclei after mitosis. These gamete 
nuclei are much larger than the progamete nuclei, thus maintaining 
the nucleo-cytoplasmic relation. Each one occupies the center of its 
gametange. The walls at the: point of contact are now resorbed. 
The nucleus from the smaller gametange (antherid) migrates into the 
larger one (oogone). 
