1058 The American Naturalist. [December, 
which group is considerably reduced in size by this new limita- 
tion. The fungi comprised under the groups above mentioned 
constitute Brefeld’s Protobasidiomycetes, in distinction to his 
Autobasidiomycetes, which form the main bulk of the order, and 
have undivided basidia. Nearly all of these latter have basidia 
of the familiar short form, with terminal sterigmata and spores; 
but in the genus Tulostoma the spores are borne laterally, and the 
basidia resemble those of Auricularia, without their divisions. 
The important point to be noted here is that the basidium fur- 
nishes the essential character of the Basidiomycetes, as was long 
ago recognized by DeBary in the very appropriafe name of the 
group, although on much less substantial morphological grounds ; 
that the basidium is more fundamental than any form of fruit 
body, and that the very various fruit forms have grown up within 
the group after differentiation of the types of basidia from their 
ancestral conidial forms. This subsequent development of the 
fruit body has produced results so striking and has followed such 
similar lines in the two great groups of fungi—the Basidiomycetes 
and the Ascomycetes—that the tendency has been to emphasize 
the differences thus brought about, with the result that we have 
lost sight of the primitive character of the basidium and the ascus. 
Among the Protobasidiomycetes we find in Pilacre a fruit form 
of angiocarpous structure, while the other forms are strictly 
gymnocarpous. Of the Autobasidiomycetes, the simplest gymno- 
carpous forms comprise the gelatinous Dacryomycetee, ‘formerly 
included in the Tremellineæ ; the Tomentellez, separated from 
the Thelephorez ; and the Clavariee. The basidium of the first- 
named family is somewhat pitchfork-shaped, with two large 
sterigmata; but in the others we meet with the typical club- 
shaped basidium, with small, spine-like sterigmata. In the 
Tomentellez we have clearly the primitive Autobasidiomycetes, 
consisting of very loose wefts of hyphz, upon which are borne, 
irregularly and indiscriminately, the basidia, which arise precisely 
as do the conidiophores of many other fungi. These pass into 
the definite fruit bodies with more or less restricted hymenial 
surface of the Clavariee and of the hemiangiocarpous families, 
he Thelephorez, Hydnez, Polyporez, and Agaricinez. Follow- 



