Mr. Woods on the Genera of European Grasses. 23 



racters. He says of the paleae of Paspalum, " inferior superiorem binerviam 

 amplectens ;" of those of Panicum, " inferior superiorem parinerviam ampiec- 

 tens." If by parinerviam we are to understand that the interior palea has the 

 same number of nerves as the exterior, it would be a curious distinction, and 

 in opposition to the general structure of the flowers of Grasses, which requires 

 a central rib in the outer palea and rejects it in the inner. This, however, 

 does not agree with the fact, and we must therefore suppose him to mean that 

 the nerves of the interior palea are in pairs, and that there is consequently an 

 even number of them, and this would not exclude the " paleam binerviam" of 

 Paspalum. In those Panicums which I have examined I find two nerves and 

 no more in the interior palea. On the whole, I confess myself unable to make 

 out any difference between Paspalum and Digitaria, for the spiculae of the 

 former seem always to be disposed in rows on the same side of a flattened 

 rachis as in the latter ; and the spiculse, as far as I can make out, are some- 

 times, but not constantly, in pairs in both genera. 



In our species of Digitaria the lowermost spiculae in luxuriant specimens 

 are three together; the upper ones are usually solitary; the intermediate ones, 

 forming the greater number, are in pairs, one of which is sessile, or very nearly 

 so, and the other stalked. This genus, as I have already said, is not admitted 

 by Kunth ; and indeed the one-sided digitate spikes, which form at once so 

 evident and so beautiful a character, would not, on the generally received prin- 

 ciples of botanical science, be acknowledged as a sufficient mark of separation. 

 Sir J. E. Smith seems rather to have endeavoured to deceive himself into a 

 belief of the difference between Panicum and Digitaria by placing Digitaria 

 among the one-flowered, and Panicum among the two-flowered Grasses, than 

 to have been really convinced of it. And while Digitaria has an additional 

 glume to the calyx, and the additional floi-et of Panicum is reduced to a single 

 valve, so very much like an additional glume that Sir James does not attempt 

 to give any mark by which they may be practically distinguished, we cannot 

 admit a separation merely on this ground Sir W. Hooker adds, that the flowers 

 are in unilateral spikes, and this is the distinction I am contending for ; and 

 I think we may be allowed to use the word spike with this latitude, though 

 some of the florets are evidently stalked. 



Oplismenus has a small point to the outer palea, and the nerves of the inner 



