Jl8 TRANS. ST. LOUIS ACAD. SCIENCE. 



With the name of longifolia I designate the variety known 

 as Sacci and extensively cultivated in Yucatan ; it is principally 

 distinguished hy its much longer spiny leaves, 4-5 \ feet long, 3- 

 4^ inches wide ; flowers very similar to those of the wild plant, 

 but filaments greenish. A. fourcroides, Jacobi, Ag. 107, proba- 

 bly belongs here, and A. elongata, Jacobi, 108, I would also refer 

 to this form if the description did not expressly mention a chan- 

 nelled terminal spine. 



Agave Sisalana is the name that Dr. Perrine gave to the plant 

 known to the natives of Yucatan as Yaxci, the most valuable of 

 the fibre-producing Agaves, and which was introduced by him 

 into South Florida some thirty-five or forty years ago, during his 

 efforts to acclimatize commercially valuable tropical plants in 

 that almost tropical portion of our territory, efforts which were 

 aided by Congress by a large grant of land, but which were de- 

 stroyed, together with his own life, during the subsequent Indian 

 wars. With this Agave, however, he has been successful, as it 

 is now fully naturalized, and is quite abundant at Key West and 

 the adjacent coast. Dr. Parry found it there in full bloom in 

 February, 1871, and gives the following description of it: trunk 

 short, leaves pale green but not glaucous, 4-6 feet long and 4-6 

 inches wide, generally smooth-edged, but here and there bearing 

 a few unequal, sometimes very stout and sharp teeth ; terminal 

 spine stout, often twisted, purplish-black ; scape 20 or 25 feet 

 high, panicle 8 feet long and half as wide ; one of the largest 

 plants examined had 35 branches in the panicle, the largest (near 

 the middle) 2 feet long, upper and lower ones shorter. The flow- 

 ers are slightly larger than those described, with a shorter, thicker 

 ovary, stamens inserted a little higher up in the tube. The plants 

 bore no fruit, but produced an abundance of buds, by which they 

 propagate themselves and from which this interesting form has 

 been multiplied in this country and in Europe. 



If this plant is, as is most probable, only a cultivated variety of 

 A. rigida, it is of the greatest importance for the study and the 

 understanding of the Agaves, indicating, as it does, the extent 

 of variation which they may undergo. It shows that the size of 

 leaf and scape, or color of leaf, are of no great specific value, 

 and also that the presence or absence of spiny teeth on the mar- 

 gin is not an unalterable character, not any more than the 



