ENGELMANN— NOTES ON THE GENUS YUCCA. 37 



are almost sessile on the older trunks, as they usually are in this 

 section ; but in vigorous young shoots they are born on a scape 

 of nearly their own length. When I examined the plants they 

 had not borne fruit for many years, though flowering abundantly ; 

 I learn that they have been fertile since, but have not obtained 

 the pods. 



There are other forms of serrulate Yuccas, most probably 

 of this section, described in the books or enumerated in the 

 catalogues of nurserymen, which are entirely unknown to me. 

 1'. serrzdata, crennlata, arcuata, tenuifolia, all named, but 

 scarcely described, by Haworth, (Suppl. PI. succ.) about fifty- 

 four years ago, from cultivated, partly very young, plants, and 

 not known now, and T. aspera, Parmentieri and albospica 

 of the catalogues, undescribed, as I believe, will probably prove 

 in part to be forms of T. aloifolia, and the names, which cannot 

 be identified now, the original types having perhaps disappeared 

 from the gardens, and their native country being unknown, ought 

 to be dropped. The two following, however, of which at least 

 their flowering state and native country are known, are believed 

 to have a claim to specific distinction. 



2. Yucca Yucatana, nov. spec. : elata, e basi ramosissima ; 

 foliis lanceolato-linearibus versus basin vix angustatis carnosis 

 brevioribus margine tenuissime asperatis demum patulis recur- 

 visve ; paniculaa ovatte subsessilis dense pubescentis bracteis 

 ultimis lanceolatis albis ; florum minorum segmentis ovato-lanceo- 

 latis, staminibus demum uncinato-recurvis ovario prismatico 

 stigmatibus parvis erectis emarginatis coronato multo brevioribus. 

 Ruins of Nohpat, Yucatan, collected in flower, Nov. 24, 1865, 

 by Dr. A. Schott, who, not only by his specimens, but also by 

 notes and sketches, aided me in drawing up this description. — 

 Habit of the plant very similar to that of the above described 

 var. conspicua; about 20 feet high, branching abundantly from 

 and near the base ; leaves in the specimens before me 14-16 inches 

 long and about 1 inch wide, thick, fleshy, smooth, but apparently 

 not rigid, with extremely slight marginal asperities ; points of 

 leaves in my specimens broken oft- Panicle densely villous, 

 bracts fleshy, whitish ; flowers spreading about 2 inches, seg- 

 ments 14 lines long, less than half as wide ; pistil similar to that 

 of T. aloi folia, but stamens much shorter and anthers smaller. 

 It is quite possible that this plant is already in cultivation and 



