CYTOLOGY OF EOCRONARTIUM MUSCICOLA 
401 
Great variation is shown also in the length of the individual cells of the 
mycelium, some cells being many times longer than others (figs. 1,2). 
The transverse septa are sharply defined. In stained material they 
cannot be easily overlooked. At or near the center of each septum 
there is usually present on one or both surfaces a large, hemispherical 
or disc-like, deep-staining body (figs. 1-4). These structures also 
occur on the septa of the hyphae making up the sporophore (figs. 
5, 6, 14, 16). They stain deeply with gentian violet and Heidenhain's 
iron alum-haematoxylin. It is interesting to note that Levine (32), 
who found what appear to be identical structures in several species of 
Boletus, states that they stain a deep red with safranin. 
These disc-like structures are described as of common occurrence 
on the cross walls of hyphae in many Basidiomycetes and certain 
Ascomycetes, and are frequently figured. They were apparently 
first mentioned by Hoffmann (22). Strasburger (49) found them in 
Agaricus campestris and states that they mark the position of inter- 
cellular pores, thus indicating protoplasmic continuity. They have 
subsequently been found by Rosenvinge (46) in Clavaria vermicularis, 
by Ruhland (47) in Lepiota lilacino- granulosa, by Harper (19) and 
Nichols (38) in Coprinus ephemerus, by Levine (32) in Polystictus 
versicolor, Polyporus adustus, Polyporus betulinus, Polyporus destructor, 
Boletus granulatus, and Coniophora cerehella, and by Kniep (27, 28) 
in Coprinus nycthemerus, Corticium varians, Corticium serum, and 
Polyporus destructor. They have also been described by Harper (18) 
in Pyronema confluens, and by the writer (11) in Rhi^ina undulata. 
They are apparently common in many of the higher fungi, but in 
certain species are stated definitely to be absent. Their occurrence 
is not associated especially with either clamp connections or hyphal 
anastomoses. The specific function of these bodies is doubtful, and no 
attempt has been made by the writer to determine their exact nature. 
The difference between the writer's results and those of Levine with 
reference to their affinity for stains indicates, however, that their 
composition is not uniformly the same. 
The cells of the endophytic hyphae in Eocronartium muscicola, 
in all the cases observed by the writer, are clearly binucleate (figs. 1-4). 
A painstaking search through many slides has failed to reveal uninu- 
cleate or multinucleate cells. Since the transverse septa in stained 
material are sharply defined, the number of nuclei in a given cell can- 
not be easily mistaken. As is to be expected, occasional cells contain- 
