322 TRANS. ST. LOUIS ACAD. SCIENCE. 



ADDITIONAL REMARKS. 



The highest trunks of cultivated Agaves which I find noticed 

 are 3-4 feet high and 3-4 inches in diameter ; the thickest one 

 was 14 inches through, but less high. I have met with no account 

 of the size they may attain in their native country. 



The scape of A. Americana is said to measure sometimes 36 

 feet in height. 



The flowers of Agave are always more or less erect and of a 

 coarser, calycine texture, while those of Yucca are pendulous and 

 corolline. 



NOTICE TO BOTANISTS. 



I wish to direct the attention of botanists, who have the oppor- 

 tunity to observe the development of these plants, to the following 

 questions : 



At what hour of the day do the anthers of the different species 

 burst and begin to shed their pollen, when do they become en- 

 tirely effete, and in what state is then the style? How long after- 

 wards and when does the style of the same flower attain its full 

 development, and when and how much do the stigmatic lobes 

 open or spread, and when does the stigmatic liquid fill the cavity 

 of the style and cover the inside of the lobes? — I have above 

 given an account of these physiological processes in A. Virgi- 

 nica ; the only reference to them in literature which I can find 

 is made by Jacobi, Ag. 310, where he says of an Agave of the 

 second section, that the full development of the style and the 

 separation and partial spreading of its lobes takes place only after 

 the stamens have faded, which, as far as it goes, fully coincides 

 with my observations. His further remark, that the stamens are 

 not inflexed in the buds of that species {A. Goeppertiana), is 

 unquestionably erroneous. Of the floral development of the 

 Agaves of the third section nothing at all seems to be. known. 



I wish also to direct the attention of observers to the time and 

 nature of the secretion of honey in the lower part of the flower- 

 tube. 



The inflorescence of those Agaves of the second section which 

 are said to bear 1 or 3 or 6-8 flowers in a fascicle requires fur- 

 ther investigation. — A careful examination of the young (form- 

 ing) inflorescences of the third section will disclose the true 

 nature of their arrangement. 



Another point which claims the attention of observers, is the 

 place and time of the formation of bulblets in the proliferous 

 Agaves. 



ERRATA. — P. 293. note, 1. 3 from "while" to end of paragraph should be carried and 

 added to the paragraph ending in "stigmas" at 1. 8, top of page. 

 P. 304, 1. 4 from bottom, strike out "to." 

 P. 314, 1. 21, for " flexi sornato," read " flexis ornato." 



