1896. ] Nash's ‘‘American Grasses.” 17 
stoups together. The study of systematic botany is a study 
of relationships. The chief end of this branch of botany is 
not to provide every plant which possesses individual variations 
with a name. It is of the greatest importance that we know 
to what known species a new one bears the closest relation- 
ship. The synonymy given under Syutherisma is faulty, if 
Wwe are to judge it by that of Doell, 5 who has furnished us the 
Most recent monograph of this group of Panicums. 
Concerning the species botanists have known for many 
years as Panicum latifolium L., but which we are informed 
Must now be called P. Porterianum Nash, Munro‘ says: ise 
P. latifolium L.! From Kalm, North America. A specimen 
attached to this from Carolina is P. divaricatum L., to which 
“From Jamaica. This plant has often been confounded with 
P. latifolium, and bears the names of P. ruscifolium, macula- 
tum, glutinosum, and agglutinans. Another specimen of d- 
varicatum is marked arborescens by Smith.” According to 
this the Linnaean name does really belong to the North Amer- 
'€an species and not to ‘a tropical species,” as stated in the 
be raised to more than varietal rank. It has a more slender 
habit than the common form of the species, but the other 
Doell in Mart. Pl. Bras, 22: 128. 1871-6. 
2—Vol. XXI.—No. 1. 
