104 NORTH AMERICAN FLORA [VoLUME 7 
5. Physopella (?) Aeschynomenis Arthur. 
Uredo Aeschynomenis Arth. Bot. Gaz. 39: 392..- 1905. 
II. Uredinia mostly hypophyllons, scattered, or grouped on small reddish spots, sub- 
epidermal, small, globose, surrounded by small paraphyses having their slender bases 
united into a firm pseudoperidinum and the capitate ends internal, opening by a central pore; 
urediniospores broadly elliptical or globoid, 14-18 by 16-23 4; wall pale-yellow, thin, 1 #, very 
minutely verrucose, pores small, obscure, about 6, scattered; paraphyses imbricated, color- 
less, 10-14 broad above where the wall is much thickened. 
III. Telia unknown. 
ON FABACEAE ; 
Aeschynomene americana I,., Morelos. 
TyPE LOCALITY : Cuautla, Mexico, on Aeschynomene americana. 
DISTRIBUTION : Known only from the type locality. 
3. BUBAKIA Arth. Résult. Sci. Congr. Bot. Vienne 338. 1906. 
Cycle of development imperfectly known; only uredinia and telia recognized, both 
subepidermal, but judging from analogy also possessing pycnia and aecia, and heteroecious. 
Uredinia erumpent, pulverulent, without peridium or paraphyses. Urediniospores borne 
singly on pedicels, obovate; wall pale-yellow, echinulate, pores obscure. 
Telia indehiscent, compacted into dense masses, several cells thick. Teliospores one- 
celled; wall colored, smooth, thin, or the uppermost thicker above. 
Type species, Melampsora Crotonis Burrill (on Croton capitatus). 
Urediniospores with uniformly thin wall. _ 1. B. Crotonis. 
Urediniospores with wall medium thick, thicker above. 2. B. mexicana. 
1. Bubakia Crotonis (Cooke) Arth. Résult. Sci. Congr. Bot. Vienne 
339. 1906. 
Trichobasis Crotonis Cooke, Grevillea 6: 137. 1878. 
Melampsora Crotonis Burrill, Bot. Gaz. 9: 189. 1884. 
Pucciniastrum Crotonis De-Toni, in Sacc. Syll. Fung. 7: 763. 1888. 
O and I. Pycnia and aecia unknown. 
II. Uredinia amphigenous, scattered, round, about 0.5 mm. across, soon dehiscent, 
cinnamon-brown, pulverulent, ruptured epidermis overarching or erect, rather inconspicu- 
ous; urediniospores obovate, 16-21 by 22-32; wall yellowish, rather thin, 1-1.5y, closely 
echinulate with short points, pores few, obscure. 
III. Telia amphigenous and caulicolous, at first arising about the uredinia, soon inde- 
pendent, scattered, irregularly orbicular, confluent, 0.5-1.5 mm. across, noticeably elevated, 
indehiscent, chocolate-brown or blackish ; teliospores united in a compact mass, appearing 
obscurely catenulate with 3-7 cells in a series, each spore elliptical or cuboidal, 10-15 by 
24-40 4, outermost longest ; wall smooth, cinnamon-brown, 3-4 thick, apical wall of outer 
spores 7-9. 
On EUPHORBIACEAE : : : 
Croton argyranthemus Michx., Florida, — 
Croton californicus Mueil. Arg., California, ; 
Croton capitaius Michx., Illinois, Mississippi, Missouri. 
Croton monanthogynus Michx., Alabama, Illinois, Indiana, Kansas, Louisiana, Missouri. 
Croton punctatus Jacq. (C. maritimus Walt.), Florida. 
Croton texensis (K1.) Muell. Arg., Kansas, Nebraska, Texas. 
Crotonopsis linearis Michx., Florida, Illinois, 
TYPE LOCALITY: California, on ‘‘ Croton procumbens,” error for C. californicus. 
DISTRIBUTION : Indiana to Kansas south to Florida and Texas, also from central to southern 
California along the coast. ; ; : ; 
ExsiccaTi: Sydow, Ured. 942, 1838; Ellis, N. Am. Fungi 1079; Ellis & Ev. N. Am. Fungi 
1877 ; Ellis & Ev. Fungi Columb. 200, 1872 ; Rab.-Wint.-Paz. Fungi Eur. 3808. 
2. Bubakia mexicana Arthur, sp. nov. 
O and I. Pyenia and aecia unknown. 
II. Uredinia amphigenous, scattered, round, about 0.5 mm. across, soon dehiscent, 
cinnamon-brown, pulverulent, ruptured epidermis overarching or erect, rather inconspicu- 
