316 TRANS. ST. LOUIS ACAD. SCIENCE. 



and £-f inch longer than the filaments, apparently already con- 

 siderably lengthened when the stamens begin lo unfold. Cap- 

 sules cuspidate but not stipitate, 2*-2f inches long, not quite i 

 inch in diameter, forming a densely packed radiating cluster, 6 

 inches in diameter ; seeds 4 lines wide. 



f f Tubus lobis vix brevior vel cequalis. 



14. Agave rigida, Mill. Diet. ed. 8, 1768 : caulescens ; foliis 

 lanceolato-linearibus glaucescentibus, margine aculeis distantibus 

 rectis parvis fuscis dentato, spina terminali valida terete saepe 

 torta basi ipsa solum paulo excavata in marginem corneum de- 

 currente ; scapo elato foliaceo-bracteato, paniculaa ovataa capsuli- 

 geras viviparaeque ram is horizontalibus ramulosis fasciculos 

 florum laxiores bracteis triangularibus brevibus stipatos gerenti- 

 bus ; ovario perigonio paulo breviore, staminibus medio tubo 

 infundibuliformi lobis paulo breviori vel supra medium insertis 

 longe exsertis stylo demum aequilongis. — Fourcroya rigida, 

 Haw. Syn. 74, Kunth en. 5, 843 ; A. atigustifolia, Haw. Saxif. 

 35 ; A. Ixtli, Karw. ap. Salm, Hort. Dyck. 304; Jacobi Ag. 95. 



Var. i.ongifolia : foliis multo longioribus glaucis, aculeato- 

 dentatis, spina terminali 11011 decurrente. 



Var.? Sisalana : foliis multo longioribus viridioribus margine 

 integris seu pauci-dentatis, spina terminali non decurrente. — 

 Agave Sisalana, Perrine, vide infra. 



The original plant was, according to Miller, brought from Vera 

 Cruz ; my specimens, on which the above diagnosis is based, 

 were collected in Yucatan by Dr. Schott. Dr. Perrine forty, and 

 Dr. Schott ten years ago, studied in Yucatan this interesting plant, 

 its different forms and economical uses, and left us accounts 

 of it, the former in Senate Doc. 300, Washington, Mar. 12, 1838 ; 

 the latter in the Report of the Agricultural Department at Wash- 

 ington for 1869. Both agree that there is a common native spe- 

 cies in Yucatan, called Chelem by the aboriginal inhabitants ; but 

 from time immemorial a number of varieties, all characterized 

 by much longer leaves, and one also by the absence of marginal 

 spines, and differing among themselves in the quantity and qual- 

 ity of their fibre, have been cultivated by the natives of Yucatan, 

 and are a staple product of that country to this day, furnishing 

 the well-known Sisal hemp. The people know them as jfene- 



