130 THE VOYAGE OF H.M.S. CHALLENGER. 



MONOCOTYLEDONES. 

 CYPERACE.E. 



Cyperus (Papyrus) atlanticus, Hemsl. (Plate XXIII.) 

 Oyperus {Papyrus) atlanticus, Hemsl., n. sp. 

 Cypero ligulari affinis, a quo differt umbellis multo densioribus, spiculis plurifloris, 

 gluruis latioribus. 



Caules 6-20 poll alti, tenuiculi, obscure trigoni, lseves. Folia caulem a?quantia vel 

 superautia, e basi lata longe attenuata, supra nuda, subtus secus costam leviter scabridn, 

 marginibus scabridis. Involucri bractese circiter 5, angusta?, inaequales, longiores usque 

 9-12 poll, longa?. Umbellce 6-12-radiata? densissima?, radiis 1-1-g poll, longis. Spicules 

 plana?, sa?pius 5-flora?, numerosse, confertissiuia?, 3-4 lineas longa?. Glumce laxiuscule 

 imbricata?, glabra?, striata?, lata?, apice subcucullata?, margine latiuscule scariosa?, dorso infra 

 apicem mucronulata?, basi appendiculata?, appendicibus demum a glumis secedentibus et 

 rbaclu persistentibus. Stylus trifidus. Nux triangularis, minutissime punctata, quani 

 glunia subduplo brevior. 



South Trinidad. — Endemic. Dry rocks near the sea — Hooker. 



Fimbristylis (Oncostylis) nesiotis, Hemsl. (Plate XXIV.) 

 Firnbristylis (Oncostylis) nesiotis, Hemsl, n. sp. 

 Oncostylo vestito et Oncostylo junciformi affinis, sed omuino glaberrima foliis multo 

 gracilioribus culmo sa?pissime longioribus. 



South Trinidad. — Endemic — Hooker. 



This plant, which was collected by Sir J. D. Hooker on the outward voyage of Sir J. 

 Ross's Antarctic Expedition in 1839, is closely allied to the two species named; yet, 

 although easily distinguished by sight, it is difficult to express the differences in words, 

 llipe nuts are wanting, or a more tangible characteristic of the species might, perhaps, 

 be adduced. There are three sheets of specimens showing the plant in as many different 

 conditions. There is the taller form (fig. A. in our plate), in which the leaves are 

 longer than the culms; and there is the dwarf form (fig. B.) with culms longer than 

 the leaves. Besides these there are two or three tufts bearins; new leaves associated with 

 the previous year's culms, which are longer than the leaves ; the latter being about a foot 

 long, and the former nearly eighteen inches. There is also one tuft of leaves, the tips of 

 which have been cut off, but which are still fifteen inches long. The flowers of only one 

 head are in good condition, the others having been eaten by insects. The very slender 

 flexible leaves and culms at once distinguish it from the relatively stout, rigid Oncostylis 

 junciformis ; and the other allied species, Oncostylis vestita, is remarkable for its hairiness. 



