Plantce LindheimeriancB. 197 



rudimento coronata ; seminibus fulvis ovatis scrobiculato- 

 punctatis. — Sterile, sandy soil on the Pierdenales : flowers 

 (in St. Louis) about the middle of June. The flowers open for 

 three days, in direct sunshine only, and later than most other 

 Cactacese, viz., from 12 or 1 till 3 or 4 o'clock. Stems 2-4 

 inches high, about 2 inches in diameter, dark green ; tubercles 

 in 13 oblique rows ; l radiant spines 3 — 4 ; central spines from 

 4-6 lines long: flowers 1§— 2^ inches long, and about the 

 same diameter when fully open, of a lighter violet color or 

 of a splendid dark purple : stigmas deep velvety purple. — 

 Very near M. vivipara, Haw., which has been found from the 

 Upper Missouri to Santa Fe : this, however, is distinguished 

 by its low, mostly ccespitose growth, by the smaller number of 

 radiant spines (14- 18), the absence of the deflexed central 

 spine, the smaller central flowers, the apiculate stigmata, 

 and smaller seeds: it also flowers earlier (in St. Louis about 

 the middle of May), but, like M. radiosa, opens the flowers 

 only after 12 o'clock. In M. vivipara the youngest tubercles 

 produce in their axils the flowers which appear central, and 

 remain so till after fructification, whereupon new tubercles 

 are developed in the centre, and the young fruit is pushed 

 aside and becomes more and more lateral. In M. radiosa 

 the flower buds are also formed in the axils of the first young 

 tubercles of the season, but are immediately pushed aside by 

 a continuous growth of more tubercules ; the buds as well as 

 the flowers and fruits are therefore lateral. M. vivipara has 

 not yet been found in Texas, though it may be expected in 

 the mountainous regions bordering New Mexico. 



§ 2. Fructu coccineo ; corolla decidua. 



* Fructu clavato elongato ; seminum testa pergamentacea, 



1 It will hardly he necessary to mention that there are several different sets of 

 rows of tubercles observable, but one set is usually more distinct than the others ; 

 they depend on the size of the plant, and the number, size, and closeness of the 

 tubercles. It is well known that in different specimens of the same species they 

 turn to either side, right or left. 



JOURNAL B. S. N. H. 26 JAN. 1850. 



