UREDINALES OF GUATEMALA 
The species appears to be closest to R. mexicana Tranz., a Mexican 
rust on Calliandra, which is yet, unfortunately, imperfectly known. 
It is also like R. versatilis (Peck) Diet., on Acacia Greggii, in its struc- 
ture, but probably has little relationship to it. 
31. Ravenelia ectypa Arth. & Holw. (on Mimosaceae). 
Calliandra gracilis Klotsch, Palin, Dept. Amatitlan, Dec. 24, 1916, 
11,111,633. 
Calliandra sp., Laguna, Lake Amatitlan, Feb. 8, 1915, ii, III, 204. 
The species also occurs in Costa Rica on C. gracilis. 
32. Ravenelia sololensis Arthur & Holway sp. nov. (on Mimosaceae). 
Lysiloma acapulcensis Benth.(?), Solola, 7000 feet alt., Jan. 28, 
1915, II, III, 147. 
Uredinia amphigenous and fruticolous, scattered, round or elliptic, 
0.2-0.5 mm. across, on the fruit up to 4 mm. long, early naked, sub- 
cuticular, pulverulent, dark chestnut-brown, ruptured cuticle con- 
spicuous; paraphyses intermixed with the spores, clavate-capitate, 
13-16 by 64-87 ijl, the wall colorless below, chestnut-brown above, 
0.5 fji thick below, 3-4 fi thick above; urediniospores ellipsoid or broadly 
obovoid, 16-19 by 27-35 fx; wall light chestnut-brown above, paler 
below, 1.5 M thick, sometimes a little thicker above, up to 3 fx, moder- 
ately echinulate, the pores 4, equatorial. 
Telia amphigenous and fruticolous, scattered, round or elongated 
elliptic, 0.2-0.4 mm. across, on the fruit up to 6 mm. in length, early 
naked, subcuticular, dark chestnut-brown, ruptured cuticle con- 
spicuous; teliospore-heads chestnut-brown, 7-9 cells across, 70-107 jj, 
in diameter, each spore with 4-6 nearly colorless spines, about 3 fj, 
long; C3^sts attached beneath the head. 
The species differs noticeably from R. Lysilomae Arth. by having 
the teliospore-heads with spines instead of smooth, and in the dif- 
ferently shaped urediniospores. It has some resemblance to R. 
Leucaenae Long, but is abundantly distinct. 
33. Ravenelia Acaciae-pennatulae Diet, (on Mimosaceae). 
Acacia pennatiila Benth., Panajachel, 5100 feet alt.. Dept. Solola, 
Jan. 30, 1915, II, iii, 162. 
Heretofore this species has been known only from collections made 
by Professor Holway in southern Mexico. 
Ravenelia Mimosae-albidae Diet, (on Mimosaceae). 
34. Mimosa albida H.B.K., Solola, 5100 feet alt., Jan. 27, 1915, II, IJT- 
The species, chiefly known from Mexico, was collected by Keller- 
