44 HISTORY AND DISTRIBUTION OF SORGHUM. 



seed varying from pale yellow to deep red. He states that these three 

 species. Holcus sorghum, II. niger, and //. saccharatus, had long- been 

 cultivated in Italy and were very variable. He calls them light 

 yielders of seed. From Holcus sorghum floor brooms were made, and 

 from Holcus saccharatus all kinds, from whisk brooms to scrubbing 

 brushes. He calls especial attention to the variability of the species 

 Holcus sorghum and II. saccharatus. While it is likely that other 

 importations than that recorded by Pliny were represented in the 

 forms described by Arduino, it is certain that many of these forms 

 must have arisen through variations and crossing which took place in 

 Europe. For many years thereafter these varying forms were made 

 the basis of new species by the botanists of that period. 



Numerous Species of Later Authors. 



Koeler (180-2) founded his genus Blumenbachia on the wild Hol- 

 cus halepensis, but the name was never taken up for the cultivated 

 plant. Brotero (1804) transferred Holcus sorghum and II. halepeu- 

 sis to the genus Andropogon. Persoon (1805) took up the old ge- 

 neric name Sorghum, first proposed by Micheli, and rechristened the 

 cultivated plant Sorghum vulgare. During the first half of the nine- 

 teenth century many more cultivated forms were described as new 

 species, until the total number of species was thirty or more. The 

 following is an alphabetical list of the names used for cultivated sor- 

 ghums described as species: Albus, arduini, besseri, bicolor, cafer, 

 caffrorum, campanum, cernuum, commune, compact us, dochna, dora, 

 drumm&ndii, duna, durra, dulcis, ferrugineus, nervosum, nigricans, 

 niger, nigerrimus, pyramidale, mtbens, saccharatus, sorghum, subgla- 

 brescens, tnnlonenorum, usorum, versicolor, and vulgare. Some of 

 these names have been used in all three genera, Holcus, Sorghum, and 

 Andropogon; some have been used in two; others only in one. In 

 this manner a total of fifty-five or sixty binomial combinations has 

 been reached. 



Most of these so-called species are quite unimportant. A few of 

 them probably include forms which have since become extensively 

 cultivated in this country. It is almost impossible to identify these 

 species from their meager descriptions, especially those described 

 from regions where sorghums are abundant and variable. In con- 

 sulting the writings of different authors who discuss a form under 

 the same specific name, it becomes evident that they did not always 

 have the same plant in hand. For example, the name bicolor of 

 Linne has at one time or another been applied to almost every form 

 with white seeds and dark glumes. In the same way the name cernuus 

 of Arduino has been used for all forms with pendent panicles, with- 

 out much regard to other characters involved. 



175 



