1907] BRIEFER ARTICLES 283 
Momordicae on M. cordijolia in Natal; (6) Aecidium Momordicae on 
Momordica in Brazil. 
The Puccinia upon Melothria pendula is different in shape, color, and 
size of spores from P. Cucumeris and from P. Momordicae, and seems 
clearly to be an undescribed species. 
The germination of the teleuto-spores 
occurs freely in the older sori, placing 
the rust among the Leptopucciniae. The 
following description is proposed. 
Puccinia Melothriae, n. sp.— III. 
Teleutosori: hypophyllous, crowded in 
irregular concentric circles, pustular, soon 
naked, pulverulent, cinnamon-colored 
(no. 32°Sacc.), cinereous on germination. 
ruptured epidermis inconspicuous; spots 
pale, indefinite. Teleutospores: hyaline 
to straw-colored (no. 26 Sacc.), 40-52 X 
10-16 w; slightly or not at all-thickened 
at apex, often not constricted at septum, Puccinia Melothriae, n. sp. 
wall about 2m thick, smooth. Terminal 
cell usually round, rarely oblong, 10-16 12-20. Basal cell wedge- 
shaped, 10-15 20-30. Pedicil 20-45 long, hyaline. Germination 
immediate; that of the terminal cell by an apical case boamaicge) that of the 
basal cell by a lateral promycelium. 
On Melothria pendula L., West Raleigh, N. C., 9-15-06, F. L. Stevens 
and J. G. Hall, type no. 471.—F. L. Stevens, West Raleigh, N. C. 
AN INSTANCE OF MUTATION 
Euphorbia marginata Pursh, commonly called in Colorado “‘snow-on- 
the-mountain,” is easily recognized by its white-margined upper leaves 
or bracts, and the five white appendages of the floral glands. In the 
splitting up of the old genus Euphorbia, it has been referred to a genus 
Dichrophyllum K\. & Garcke, and distinguished from Tithymalus Adans 
by the characters just mentioned. In Tithymalus there are but four glands, 
with rudiments of the fifth. All authors seem to agree that E. marginala 
has five glands; “three” in Britron and Brown, Jil. Flora 22376, isa 
mere misprint, as the figure shows. Having recently had gccasion to 
examine E. marginata at Boulder, Colorado, I have been astonished to 
find that four glands is normal in this locality, and a plant with jive glands 
