Ml!. 6. BENTUAil Oif GHAMINEJi. 93 



genus some species of Isachne Lave been referred, but from -whicli 

 they constantly differ in the empty glumes persistent below the 

 articulation, and in the two flowers both hermaphrodite or female, 

 though one may be occasionally sterile. Graya, Nees (judging 

 from the reference lo Wight, but not from Steudel's characters) 

 is Isacfine pulcliella, lioth {Panieum helium, Steud., P. malaccense, 

 Trin.). Fanicum Qardneri, Thw., which, as the author observes, 

 is closely allied to Isachne Wallceri, Wight, appears to me to bo 

 strictly congener with that species, although one of the flowers of 

 the spikelet is frequently, but not always, sterile. It seems to be 

 the same as Isachne nilaghirica, Hochst. 



3. Zenkeeia, Trin., very well described and figured in the 

 'Linnsea,' vol. xi., now contains two species from the East-Indian 

 peninsula and Ceylon, both very near Isachne, but with membra- 

 nous fruiting glumes. Amphidonax Seynei and A. fenella, Nees, 

 do not differ from the typical Z. elegans, Trin. The second spe- 

 cies is Z. oltusiflora {Amphidonax ohtusiflora, Thw.). The ori- 

 ginal genus Amphidonax of Nees was founded on a species of 

 Arundo. 



4. MiCEAiEA, if. Muell., is a single North-east Australian spe- 

 cies recently figured in Hooker's Icones. 5. Coslachne, Br., 

 comprises three East-Indian, Chinese, or East- Australian species^ 

 G. pulchella, Br., C. perpwsilla, Thw., and O. simpliciuscula, Munro 

 {Isachne simpUciuscula,'Wight et Arn.), which, as above observed, 

 are anomalous in the tribe by a slight extension of the rhachilla 

 between the flowering glumes. 6. Aieopsis, Desv., restricted to 

 the single West-Mediterranean A. globosa, is a pretty little 

 annual, formerly placed in Milium on account of the hardening 

 of the glumes, or in Aira, which it resembles in many respects. 

 It shows, however, all the characters of Isachnese, and is indeed 

 technically nearly allied to Isachne itself ; but the two semiglobose 

 fruiting glumes, closely appressed to each other by their flat 

 faces, give the spikelets the peculiar globular shape expressed by 

 the specific name. 



7. Eeiachne, Br,, comprises twenty-two species, two of them 

 endemic in tropical Asia, the remainder Australian, of which one is 

 also in East India. They diff'er from Isachne generally in their 

 rather larger spikelets, and especially in the long hairs on the back 

 or margins of the flowering glumes, and sometimes in the fine 

 straight awns terminating the flowering glumes, or even the teeth 

 of the paleffi. Megalachne, Thw. (not of Steud ), is Uriachne triseia, 



LIHK. JOUKN.— BOTANT, TOL. XIX. I 



