308 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



late, the lower surface bearing yellowish glands; petioles densely stellate-pubescent; 

 flowers and fruit appearing before the leaves, borne on short (3 to 5 mm. long), thick 

 peduncles from near the tips of branches of the previous year; bracts ovate, 2 to 3 mm. 

 long; calyx 5 or 6 mm. long, densely stellate-pubescent as are also the bracts and 

 pedicels; corolla 4 cm. long, deep purple with a large dark, nearly black spot at base; 

 capsule 25 mm. long, purplish, covered with large black glands; seeds 6 to 7 mm. 

 long. 



Type U. S. National Herbarium no. 037875, collected by Rose, Standley, and 

 Russell near Culiacan, April 22, 1910 (no. 14999). The same was collected by E. A. 

 Goldman near La Rastra, Sinalou, March 9, 1899 (no. 267). 



This species was common along the Mexican branch of the Southern Pacific Rail- 

 road between Mazatlan and Culiacan, Sinaloa. It grows on the dry hills among 

 stunted shrubs and trees. 



Erioxylura palmeri Rose. 



Cienfugosia palmer i Rose, Contr. Nat, Herb. 1: 308. 1895. 



Only known from the type collection which came from near Colima, Mexico. 



CACTACEAE. 



A NEW SPECIES OP ARID-CARPUS FROM MEXICO. 



The genus Ariocarpus is generally supposed to contain but five 

 species, although one or two additional ones are sometimes offered 

 by the trade. Ariocarpus fur furaceus and A. retusus are much alike 

 and are often confused in collections, but as they are very different 

 from the one here described may be passed over for the present. 

 Ariocarpus Jcotschubeyanus, although somewhat similar to A. 

 fissuratus in structure, is always small and is of course quite distinct. 

 The new species described below, however, usually passes as A. 

 fissuratus and in fact is the only representative of that species in 

 many collections. The true A. -fissuratus (pi. 62) came from near 

 the mouth of the Pecos River in western Texas, where I obtained 

 some typical specimens in 1908 and whence I afterward obtained an 

 unusually large plant through Mr. M. Dodd, an enthusiastic cactus 

 collector. These specimens are all so similar to Engelmann's illus- 

 tration of his type and so different from all the Mexican material 

 seen that I have no hesitancy in basing a new species on the material 

 furnished by F. E. Lloyd from the State of Zacatecas, Mexico. 



Ariocarpus lloydii Rose, sp. nov, Plate 63. 



Plant body low with rounded top, 10 cm. or more in diameter, tapering below into 

 a very thick root; tubercles imbricate, 2 cm. broad at base, the upper portion rounded, 

 obtuse, broader than thick, the whole surface fissured but not in definite bands; areoles 

 filled with a dense mass of hairs; flowers purple, about 3 cm. long; petals broad, 

 apiculate; styles .slender, longer than the stamenR. 



Type U. S. National Herbarium no. 535137, collected by Francis E. Lloyd on the 

 Hacienda de Cedros, Zacatecas, Mexico, 1908 (no. 34). The photograph was taken in 

 Washington. 



This species is different from A. fissuratus in the shape and surface of the tubercles. 

 In the latter species the corrugations are broken up into bands, the outer ones forming 

 an elevated margin, while in A. lloydii they are equally distributed over the surface. 

 Plants of A. lloydii are not flat and have a more southern range. 



