472 
J. C. ARTHUR 
but we may fairly infer that the hosts of both the Guatemalan and 
Surinam collections are species of Stigmaphyllon, or at least that they 
belong to the Malpighiaceae. The rust may be characterized as fol- 
lows : 
Uredinia amphigenous, scattered or in groups 2-3 mm. across, 
round or oval, 0.3-1 mm. across, rather tardily naked, pulverulent, 
cinnamon-brown, ruptured epidermis conspicuous; urediniospores 
when dry or in alcohol broadly ellipsoid or globoid, 22-26 by 26-32 jjl; 
wall golden or dark cinnamon-brown, 2.5-3 M thick, very sparsely and 
prominently echinulate, the echinulations 2.5 /jl long, i /jl wide at 
base, 7-10 M apart, and colorless, the pores 2-4, equatorial; uredinio- 
spores when in water swelling to 27-32 by 32-40 ^t; wall 5-7 fx thick, 
with a cinnamon-brown inner layer 3-4 fx thick and a colorless outer 
layer 1.5-4 M thick. 
Telia amphigenous, scattered, blackish-brown; teliospores broadly 
ellipsoid, 26-35 by 35-50 m» rounded at both ends, slightly or not 
constricted at septum; wall dark chestnut-brown, uniformly 3-4 
thick, rather obscurely reticulate, the areolae about 2-3 fi across; 
pedicel usually attached obliquely, once to once and a half length of 
spore, in water forming a globoid swelling next the spore up to 26 in 
diameter. 
130. PucciNiA EuPHORBiAE P. Henn. (on Euphorbiaceae). 
Aklema caracasana (Klotzsch & Garcke) Millsp. {Euphorbia 
caracasana Boiss.), Guatemala City, Dec. 31, 1914, II, III, j; 
Antigua, Dept. Sacatepequez, Jan 11, 1915, ii. III, 66; same, 
Dec. 27, 1916, II, III, 641 ] Quezaltenango, Jan. 18, 1917, 
III, 740. 
A long-cycle rust, having pycnia, uredinia, and telia, with large 
and highly characteristic teliospores. It is the form designated by 
the Sydows as variety longipes, but agrees with the type material 
from Abyssinia. It was also collected by Kellerman, on Aklema 
cotinifolia (L.) Millsp. (Euphorbia cotinifolia L.), at San Lucas, Dept. 
Solola, Feb. 16, 1906, II, III, 54JJ. It occurs in Mexico and the 
West Indies. 
131. Puccinia velata (Ellis & Everh.) comb. nov. (on Euphorbiaceae). 
Aklema Scotana (Schlecht.) Millsp. {Euphorbia Scotana Boiss.) 
A phanerogamic specimen of this host in the Field Museum at 
Chicago, 111., sheet number 195471, shows the rust named. It was 
collected at San Lucas, Dept. Solola, Feb. 16, 1906, by Kellerman, 5433, 
and there are both uredinia and telia present. 
