146 RYDBERG: SOLANUM IN MEXICO AND CENTRAL AMERICA 
species, this division was very artificial. Bitter, who in 1812-15 
published such valuable contributions to the knowledge of 
Solanum and especially of this very section, substituted instead 
the mode of articulation of the pedicels as the main bases of 
classification of this section, and established two subsections: 
BASARTHRUM, with basal articulation, and HYPERBASARTHRUM, 
with the articulation higher up. He also pointed out that the 
latter could be subdivided by the shape of the fruit, subconic or 
subglobose, and the deeper or shallower division of the corolla. 
Following these suggestions and elaborating on the same, I have 
been able to present the following key of the Mexican and Central 
American species as far as they are known to me. 
Bitter, following more or less the German fashion of classify- 
ing the different forms of a genus in many categories, used the 
ranks: superspecies, or collective species, species, subspecies, 
variety,and forma. In most cases I have regarded his subspecies 
as distinct species, admitting, however, that each is most closely 
related to the species of which he made it a subspecies. In most 
cases I have not regarded it worth while to pay special attention 
to his varieties or formas. In one case, however, I think, a cer- 
tain variety deserves specific rank, better than some of his sub- 
species and even better than one of his species. 
Key 
Pedicels articulate some distance above the base 
Na aborenedtogs ip 
Stem her 
Fruit seetige or a rounded at the apex; 
plants with tu 
Leaves pinnatifid. 
Corolla 5-agonal, its lobes as broad as or 
broader than tong... 6. a, oe I. TUBEROSA.” 
Corolla distinctly star-shaped, its lobes 
longer thari broad... oo 345.2 32722 2. PINNATISECTA.” 
Leaves simple; corolla star-shaped.......... 3- BULBOCASTANA.- 
Fruit elongated-ovoid or sub-conical, acute at 
the apex; plant probably not tuber-bearing.. 4. OXYCARPA 
S woody, climbing; plant not tuber-bearing... 5. JUGLANDIFOLIA.» 
paseo articulate at or near the base; plant not 
tuber-bearing as faras known. (BASARTHRUM). 
Stem herbaceous......... 8 -  e 6. SUAVEOLENTIA. ° 
Stem woody, climbing and rooting at the nodes.. 7. APPENDICULATA.” 
