2GS THE VOYAGE OF H.M.S. CHALLENGER 



Perenne stoloniferum, undique glabra, stolonibus brevibus. Culmi adscendentes, 

 graciliusculi, 9-18 poll, longi, supra paucifoliati. Folia tenuia, lasvia vel margine leviter 

 scabrida, plana, basi latiuscula (2-2^ lineas), acutissima, absque-vagina 1-3 poll, longa, 

 in loco ligulae ciliolata. Panic u Icb compactse, 1^-3 poll, longae, f-1^ poll, latae, longiuscule 

 pedunculate; spicules breviter graciliterque pedicellatae, 2-florae, cum aristis 7-8 lineas 

 longae. Flores bermaphroditi, basi pilosuli ; glumae scariosas, uninerviae, 2 exteriores 

 lanceolatae, longe acuminate vel pseud oaristatae, carinatae, secus carinam leviter scabridae ; 

 gluma florens absque aristis exsertis duplo brevior, apice triaristata, vel bisetosa cum 

 arista inter setas terminalis, arista propria torta, geniculata, setas laterales triplo 

 superans ; palea angustissima glumam aequans ; stamina 3. Caryopsis libera, anguste 

 oblonga, glabra. 



St Paul. — Endemic. Frequent in the low grounds, rare on tbe summit — MacGillivray 

 and Milne; without locality — Lieut. A. J. Smith; the earliest flowering plant in the 

 island — De I' Isle, 1. 



We suspect this is the plant referred to by Reichardt under the above name, though it 

 is perfectly distinct from the typical plant in Kew Herbarium. We have placed it in the 

 genus Trisetum in spite of its having a terminal instead of a dorsal awn, because we 

 believe that Danthonia must eventually be reduced to the former genus. Among plants 

 in the two genera there exists every gradation from a strictly dorsal awn to a terminal 

 one, as in our plant, between the two lateral setae. Trisetum insulare is most nearly 

 allied to the South African Danthonia papillosa, Trin., which, however, is a very hairy 

 plant. Aira pictiglvma, Steud., now referred to Trisetum, is a very similar plant from the 

 mountains of Tropical Africa. There are two flowered species with a dorsal awn, and there 

 are two flowered species with a terminal awn in both genera ; and as the genera have been 

 limited, one finds the same range of variation and parallel forms in the two. 



Agrostis difflcilis, Hemsl. (Plate XLIII.) 

 Agrostis difficilis, Hemsl., n. sp. 



Caespitosus, erectus, glaber, laevis, folds teniusculis planis, spiculis minutis, glumis 

 muticis exterioribus fere aequalibus. 



Perennis, 1^-2 pedalis, culmis graciliusculis. Folia radicalia non visa, caulina acuta, 

 3-6 poll, longa, ligula ampla, Integra, rotundata. Paniculce graciles, angustae, pedicellis 

 parcissime et minutissime puberulis. Glumce glabrae, vel exteriores pilis paucissimis secus 

 carinam instructs, acutae ; florens paulo brevior, obtusa, integra ; palea obtusa ; stamina 

 3. Caryopsis matura non visa. 



Amsterdam Island. — Endemic. Rather common in humid parts of the low ground 

 — De I'Isle, 37. 



