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1894.] The Homologies of the Uredineae. 
CLASS ASCOMYCETEAE. 
Order Perisporiaceae, 
Order Tuberoideae, 
Order Pyrenomyceteae, 
Order Discomyceteae, 
Order Uredineae, 
Order Ustilagineae. 
CrLAss BASIDIOMYCETEAE. 
Order Gasteromyceteae, 
Order Hymenomyceteae. 
Of the relationship of the Uredineae to the Ustilagineae I 
need say no more at the present time than that the latter are 
here regarded as still further degradations of the Discomyceteae; 
nor is this the place in which to take up a discussion of the 
homologies between the Ascomyceteae and the Basidiomyceteae. 
Upon the latter point it is sufficient to say that the ascus and 
the basidium are regarded as morphologically equivalent, the 
ascus subdiving its protoplasmic contents into spores by an 
internal division (forming ascospores) while the basidium 
accomplishes the same thing by the growth of protrusions 
(“ sterigmata ") into whose enlarged ends the protoplasm passes, 
after which they separate as spores (basidiospores). 
ExPLANATION OF Prare XXXII. 
I. Cross section of a Barberry leaf; a, a cup of aecidio- 
spores; b, spermogones of Puccinia graminis, after 
Luerssen X 
II. Rows of aecidiospores (conidia) of P. graminis upon their 
conidiophores, after De Bary x 150. 
III. Uredospores of P. graminis, the shaded one ripe, after 
De Bary, x 390. 
IV. Germinating uredospore of P. straminis, after De Bary, 
X 390. 
V. Cross section of a teleutosorus of P. graminis, after De 
Bary, X 200. 
