82 PANICACE.E. 



entirely deficient in tlie section Digitaria; consequently several 

 species have been referred by some botanists to one genus and by 

 others to the other. These ambiguous species appear to be best 

 placed in Panicum. 



All the true Paspala have the spikelets sessile or nearly so, in 

 two to four rows along the lower or outer side of the rachis or 

 simple branches of the panicle. Scarcely five species can be regarded 

 as belonging exclusively to the Old World. General Munro had 

 nearly completed a monograph of the genus, leaving descriptions of 

 138 species. He and Dr. Bentham agreed perfectly in not making 

 species to show all slight variations, corresponding to what many 

 local Eurojiean botanists describe as critical species. 



Trinius subdivided the genus, chiefiy according to the size of 

 the spikelets. 



Bentham and Hooker adopted three sections, founded on Nees's 

 — EujmsjKihim, Cabrera, and AnasU^oplins, subdividing the first and 

 much the largest into four groups — Anachyris, Ojnsthion, Pseudo- 

 ceresia, and Ceresia. 



Anachyris is a purely artificial one, characterized solely by having 

 only a single empty glume below the flowering one. It was first 

 proposed as a genus by Nees for Pasjjalnm malacophylhim Trin. 

 Opisthion was proposed by Doell as a section of Paspahwi, 

 but Bentham and Hooker use it as a name for a group. It in- 

 cludes all the typical Paspala with two lower empty glumes, and 

 tlio rachis of the spikes not dilated. The species are numerous and 

 varied. Pseudoceresia is the name of the group of species in which 

 the rachis of the spikes is more or less dilated and concave, but 

 green and herbaceous throughout, and the spikelets are small and 

 glabi'ous or nearly so. The species are few, including P. repens 

 Berg, and its allies. Ceresia is the name proposed for a genus by 

 Persoon. Here the dilated rachis of the spike is bordered by a 

 coloi'ed or sniootli membranous margin and the half-enclosed 

 spikelets are larger thau in Pseudoceresia and densily ciliate. 

 Cabrera, the second section of Pasalum, contains a single species, 

 P. aureum H.B.K., forming Lagasca's genus Cahrera. In thi.^ 

 the directioii of the spikelets is nearly that of Anastrojihns ; but 



