BOTANY. 347 



Sorghum. Besides these, is A. Drummondii, Nees, from New Orleans. These 

 so-calkd species are, in all probability, founded on permanent varieties of 

 the grass which has been grown for its grain and foliage for centuries in the 

 East Indies and Africa. It was placed first in the genus Holcus by Linnasus, 

 but has been separated from it and ranked in that of Andropoyon. It is still 

 kept there by some of the best botanists of the day ; but by others it is 

 placed in that of Soryhum, a genus separated from Andropoyon mainly from 

 its paniculate inflorescence and coriaceous glumes. The species named for 

 Druinmond, by Nees, is probably a form of the same plant which had estab- 

 lished itself at New Orleans. An authentic specimen in Dr. Gray's herba- 

 rium does not appreciably differ from some of the varieties grown in South 

 Carolina. 



The thirty-one specimens laid before you are thought to represent four 

 species, and many varieties. The seeds came from France, but the plants 

 furnishing them originally came from widely separated localities. The dif- 

 ferences which they exhibit are in the color, shape, and hairiness of the 

 glumes; the color, shape, and prominence of the corn beyond the glumes; 

 and the open or compact growth of the panicle. If these differences were 

 constantly exhibited together, if the difference of shape were always 

 attended by a difference in color, and that color always accompanied by the 

 same hairiness and exsertion of corn, there would be strong ground to 

 establish specific differences. But such is not the case. The specimens, 

 placed side by side, exhibit a complete gradation between the extremes of 

 the series. Those which vary most in shape are similar in color. Those 

 which differ in color are identical in shape. The hairiness and the degree of 

 exsertion are coexistent with the extremes of shape and color. There are 

 four which are especially interesting. Mr. Olcutt grew Broom Corn and 

 Dourrha in rows on each side of Soi'gho sucre. The result was a plant partak- 

 ing equally of the characteristics of the parents on each side. The eighteen 

 varieties of Imphee, thought to be so distinct that different native names 

 have been given them, exhibit every intermediate form imaginable. Some 

 glumes are nearly white; some are specked with brown and black; some 

 are all brown; others all black. Some have ovate pointed glumes of every 

 hue; others have obtuse glumes, with a broad, scarious point, or rounded 

 glumes Avith no point, through the same series of color. The corns are 

 either enclosed or exserted through the Avhole series, irrespective of color or 

 form. Some of the varieties of Imphee present a peculiar appearance, from 

 the persistence and prominence of the sterile spikelets; some, differing in no 

 other respect, have these scarce visible; and some have them not at all. 

 Color and hairiness are among the least reliable of botanical characters, and 

 should have but little Aveight in plants so closely allied; and the other differ- 

 ences are exhibited almost as prominently in different panicles of the same 

 acknoAvledged variety. 



The question of the hybridity of species of plants has lately received close 

 and careful attention. M. Charles Naudin has recently made a series of 

 interesting experiments on the cultivated pumpkins and squashes. He has 

 arrived at the conclusion, that nearly all those grown in our gardens may be 

 referred to one single species. He has particularly examined the changes . 

 which artificial impregnations Avill produce. We often hear that cucurbita- 

 ceous plants should not be grown together, or they Avill injure each other. 

 This gives rise to the question, Avhether the fruit of the same season can 

 acquire another's peculiarities without first being grown from the seed, the 



