320 TRANS. ST. LOUIS ACAD. SCIENCE. 



ened at the apex, interior shorter, broader and thinner ; nectarif- 

 erous part of tube, below the insertion of the stamens 25-3 lines 

 long, a little longer than upper part of tube ; exsert part of fila- 

 ments about the length of perigon, anthers 8 lines long ; capsules 

 slender, 18-24 lines long, 7-8 wide ; seeds among the smallest of 

 this section 2 J lines in the longest diameter, easily distinguished 

 by the minute tubercles, 0.0 1 line wide, which, different from 

 other Agave seeds, cover the surface. 



16. Agave Wislizeni : acaulis ; foliis ovatis supra basin paulo 

 angustatis medio latissimis acutis, spinas subflexuosae supra late 

 exarataB margine acutiusculo decurrente, dentibus rigidis atro- 

 fuscis superioribus majoribus distantibus rectis, inferioribus 

 parvis confertis subdeflexis ; panicula laxiflora ; ovario perigo- 

 nium et tubo lobos fere asquante, staminibus ultra medium tubo 

 adnatis longe exsertis ; capsula gracili prismatica utrumque acuta 

 nee stipitata, areolis seminum planis punctulatis. — A. scadra, 

 Salm, Bonpl. 7, 89 ; Jacobi, Ag. 88. 



This interesting species was discovered by Dr. A. Wislizenus 

 on the celebrated march of Doniphan's corps through Northern 

 Mexico, on the Nazas River near San Sebastiano, in the south- 

 east corner of the State of Chihuahua, not far east of Parras, May 

 10, 1847, in fl. and fr. Living shoots were sent by me to Prince 

 Salm and seeds to different European correspondents, among 

 others to Prof. A. Braun of Freiburg. Two years later Gen. v. 

 Jacobi obtained some of the young plants raised from these seeds 

 in the botanic garden of that university and afterwards commu- 

 nicated them to Prince Salm, who described them (1858) under 

 the inappropriate name A. scadra, though, as the General ex- 

 pressly states, they are perfectly smooth on both sides.* As thus 

 the published name is inadmissible, I deem it proper to substitute 

 for it that of the discoverer of this and so many other interesting 

 plants of Northern Mexico. 



Jacobi describes his specimens (then 16 years old, and, as he 

 thinks, full grown) as 8 inches high and 15 in diameter, rosulate 

 and somewhat squarrose, with broad, nearly rhombic and almost 

 flat leaves, 5 inches long, 3* wide, pale grayish-green, teeth distant 



* Agave asperrima, Jacobi. is one of the few rough ones, and the only hairy one known, 

 I believe, is A. pubescens, lately described by Regel. This species, obtained from Mexico 

 and flowered at St. Petersburg, is one of the smaller ones and seems to belong to the first 

 section. 



