146 ARTHUR: NEW SPECIES OF UREDINEAE 
intermixed, doubtless of uredinial origin, often wanting; telio- 
spores apparently in groups, ellipsoid or oblong, 16-21 by 28-35 n, 
rounded at both ends, deeply constricted at the septum; wall dark 
chestnut-brown, uniformly 1.5-2 4 thick, moderately and closely 
verrucose with conical warts, at times almost echinulate; pedicel 
short, colorless, fragile. 
On Viorna sp., Abilene, Texas, May 17, 1900, T. A. Williams. 
The specimen, which was communicated by the National Museum, 
Washington, D. C., has been in hand for a considerable time, 
hoping that additional material would come to light. The ap- 
pearance of the rust is much like that of species belonging to the 
genus Tvranzschelia, but the uredinial stage is yet imperfectly 
known; moreover, the pycnia are unequivocally subepidermal. 
It finds its nearest representative seemingly in Tranzschelia cohaesa 
(Long) Arth. (Puccinia cohaesa Long), a species from Texas on 
Anemone. But not only are the pycnia subepidermal, both pycnia 
and aecia are grouped instead of systematically scattered. It 
might be assumed that the aecia here described, which occur upon 
the leaves and are entirely dissociated from the caulicular telia, do 
not belong to this species, but are heteroecious and the aecia of 
Puccinia Agropyri E. & E., which occur upon species of Viorna 
further north, and are common in Texas on Clematis Drummondii. 
However, the aeciospores measure much smaller than those of any 
collection known for that species. An interesting feature is the 
grouping of the teliospores, which can be fairly well seen in sections 
of sori, which have not yet opened. It is a character exactly in 
accord with the telial characters selected for the genus Tranz- 
schelia. The paraphyses are also essentially like those of that 
genus, both in form and position in the sorus, and the uredinjo- 
spores as well. The characters of the latter can not, however, be 
fully made out until the uredinial sorus is studied. Altogether it 
would seem that in this new and highly distinctive ranuncula- 
ceous species of rust we have another candidate for the genus 
Tranzschelia, and one which will necessitate some modification in 
the generic characters. 
Puccinia missouriensis sp. nov. 
O. Pycnia epiphyllous, few in small groups, honey-yellow, in- 
conspicuous, subepidermal, flask-shaped, 60-75 4 in transverse 
diameter, with ostiolar filaments. 
