140 LEVINE: CYTOLOGY oF HYMENOMYCETES 
the basidium of Russula rubra, and Rosenvinge (1887) extended 
this conclusion to thirty-five species of Basidiomycetes. Rosen 
(1892) working on material from Lepiota mucida first observed 
nuclear fusions in the basidium. He concluded, however, that 
the secondary nucleus of the basidium resulted from the fusion 
of six or eight nuclei coming from the hyphae of the lamellae. 
Wager (1893-’4-’9) gave us the basis for most of our present 
day conceptions of the nuclear phenomena in the basidium. 
He followed Rosen in the conception that more than two nuclei 
may fuse in the formation of the secondary nucleus of the basidium 
(see table, p. 164). He even suggests the probability of a number 
of nuclear fusions occurring before the primary nuclei pass into 
the basidium. Wager observed that in the fusion of the nuclei 
their chromatic reticula become intermingled and that the nucle- 
oles finally fuse. He describes the nuclei of the basidium as 
having the typical structures found in higher plants, such as, 
chromatin, linin, differentially stained nucleoles, nuclear mem- 
branes, etc.; and was able to make out karyokinetic division 
figures. How the spindle is formed Wager could not make out, 
but believes that it comes in some fashion from an archoplasmic 
body. The chromosomes are six to eight in number. 
Dangeard (1895) was the first to establish the fact that only 
two nuclei fuse to form the secondary nucleus in the basidium of 
Tremella mesenterica, Dacryomyces deliquescens, Calocera viscosa, 
Craterellus sinuosus, Bovista plumbea, Nyctalis parasitica, Hydnum 
repandum, and Polyporus versicolor. He was the first also to 
affirm the sexual nature of this nuclear fusion in the basidium as 
well as in the ascus, the teleutospore, and the spore of the smuts. 
On these facts he bases his well-known doctrine that the Usti- 
lagineae, Uredineae, Basidiomycetes, and Ascomycetes have 4 
sexuality which is essentially equivalent to that of the higher 
animals and plants. Dangeard claims that the young ascus, the 
young basidium, the teleutospore, and the smut spore are odgones 
and develop in one of the following ways. In the first case, 
the egg germinates by producing a promycelial outgrowth which 
produces sporidia endogenously as in the ascus, or exogenously 
as on the promycelium of the teleutospore and smut spore. In 
the second case the egg becomes segmented into a number of - 
