UREDINALES OF GUATEMALA 
probable that the fragmentary collection which served as the type of 
the species is really an Acacia and not Leucaena. The type shows 
only a few imperfect urediniospores, while the present collections have 
well developed uredinia. 
The uredinia are hypophyllous, on purple spots, round, 0.2-0.5 
mm. across, early naked, somewhat pulverulent, cinnamon-brown, 
with the ruptured epidermis evident. The urediniospores are oblong 
or elongated ellipsoid, 13-16 by 26-35 M» the wall cinnamon-brown, 
1-1.5 iJL thick and somewhat thicker above, about 3 /z, moderately 
echinulate, with 4 equatorial pores. The few spores heretofore seen 
did not show the thickening above, or the true form and size. The 
paraphyses intermixed with the spores are erect, clavate-capitate, 
10-15 by 50-77 IJL, with the wall chestnut-brown above and colorless 
below, and from 0.5 jj, thick at the sides to 3-5 ju thick at the apex. 
The species differs from R. australis Diet. & Neg., and from Uredo 
Hieronymi Speg., both on Acacia Farnesiana, in the paraphyses, and 
also in the urediniospores. Long^ has recently found R. australis in 
Texas, and gives a detailed account of the species. The two species 
are similar in many respects, as noted in the North American Flora 
(7* I34)» but the urediniospores of R. Leucaenae-microphyllae are more 
slender, and the paraphyses are erect and capitate, not at all incurved 
and hyphoid as in i?. australis. 
27. Ravenelia igualica Arth. (on Mimosaceae). 
Acacia angustissima (Mill.) Kuntze {A. filicina Willd., A. filicu- 
loides Trel.), Quezaltenango, Jan. 21, 1915, III, p/; Solola, 
7000 feet alt., Jan. 25, 1915, II, III, iiQ. 
The species has been taken heretofore but a few times between 
Texas and southern Mexico. 
28. Ravenelia inquirenda Arthur & Holway sp. nov. (on Mimosaceae). 
Acacia bursaria Schrenck, Laguna, Lake Amatitlan, Feb. 8, 1915, 
II, ig6. 
Uredinia amphigenous, scattered or somewhat grouped, roundish, 
0.1-0.3 mm. across, somewhat tardily naked, subepidermal, opening 
by a slit or pore, pulverulent, cinnamon-brown, ruptured epidermis 
conspicuous; paraphyses intermixed with the spores, cylindric or 
clavate-capitate, 7-10 by 26-42 fx, the wall cinnamon-brown, uni- 
formly about 0.6 fjL thick; urediniospores ellipsoid or obovoid,_i5-i8 by 
^Bot. Gaz. 64: 65. 1917. 
