108 Me. G. BENtHAli ON OlUMlNEji. 



plants a different habit from that of the several preceding genera. 

 The species may be distributed into two rather distilict sections. 

 (1) Pseuclocynoclon, with only one or two flowers in the spikelet, dif- 

 fering hut little from Gynodon except in inflorescence. To this sec- 

 tion heloiigL.uniJlora, Tloch.sb.(Ci/nodonffraoilis, Nees), from Abys- 

 sinia, Ii. Neesii {Gynodon Neesii, Tlnv.), from Ceylon, and L. poly- 

 stachya, Beuth. {Qynodon polystachyus, Br.), from Australia. (2) 

 Euleptochloa, with two or more flowers to the spikelet, comprises 

 the remainder of the species. Tliose which have a point or short 

 awn to the flowering glume were formerly generically separated 

 by Beauvois under the name of RabdooMoa. Amongst the pub- 

 lished species, L. arabica, Kunth, is the genus Dlnelra ; L. Lind- 

 leyana and L. mollis, Kuuth, are referable to Triodia. L. duhia, 

 Nees {Chloris duhia, H. B. K.), and the North-American L. (Di- 

 plachne) fascicularis , A. Gray, appear both to be true species of 

 Diplachne. Lorentz's South-American plant disti-ibuted by G-ri- 

 sebach as L. fascicularis appears to be a mere variety of Panicmn 

 sanguinale. L. Wightiana, Noes, is an JSragrostis. L. plu- 

 mosa, Anders., is a Triodia. 



There remain three anomalous monotypic genera from the 

 Mexican-Texan region — 25. BucnLOE (Sesleria, afterwards Oalan- 

 thera, Nutt.), 26. Jouvea, Fourn., and 27. Opizia, Presl, which 

 connect in some measure Chloridese with the subtribe Sesleriea', 

 and are all dioecious, and very remarkable for the great dissimi- 

 larity in the spikes and spikelets of the two sexes. Of the first, 

 numerous specimens fully confirm Engelmann's excellent jigures 

 and description ; the other two are unknown to me, and remain 

 somewhat doubtful. Of Jouvea, Pournier only knew the female, 

 which he says is allied to BucMoc, with a very different habit. 

 Opizia is said by him to have the male plant exactly like Buchloe ; 

 the female figured by Presl must be very different, though his 

 and Pournier's descriptions do not agree in all points. ' 



Tribe XII, EESTtrcEiE. 



The large tribe Festticea presents considerable difficulties to 

 the systematist. Of the seventy genera on our list (about a 

 hundred and ten of some botanists), the greater number are perhaps 

 better defined than those of Agrostese for instance, and afibrd a 

 much greater variety of characters ; but none of the various 

 arrangements' proposed for distributing them into groups or sub- 

 tribes have proved satisfactory, and the two largest genera Poa 



