REPORT ON THE BOTANY OF THE ISLANDS OF THE SOUTHERN OCEAN. 155 



CTPERACE/E. 



Scirpus. 



The forms of this genus in Tristan da Cunha and the neighbouring islets, Inaccessible 

 and Nightingale, are numerous, and so closely allied, most of them, to each other, that it is 

 a difficult and perplexing task to deal with them. Nearly a dozen of them have been 

 described as species, or perhaps it would be more correct to say that about that number 

 has been proposed, for some of the forms, doubtless, have been described under more than 

 one name. Of the forms collected by Mr Moseley, Bceckeler described five as new species ; 

 only one of which, Scirpus oliveri, in our opinion, has any claim to that rank. These 

 sedges are very abundant in the islands, growing in a variety of situations ; hence, pro- 

 bably, the differences in habit, vigour, degree of fertility, and other characters which have 

 been regarded as of specific value. We have devoted four plates to the illustration 

 of some of the more distinct forms, which we reduce to four species ; and we think it 

 probable that a careful study of all the southern species would lead to the identification 

 of some or all of the insular forms with some of the South African, Australian, or 

 New Zealand species. 



Scirpus sulcatus, Thouars. (Plate XXXI.) 



Scirpus sulcatus, Thouars, Esquisse Fl. Trist., p. 36, t. 7, fig. dextra; Kunth, Enum., ii. p. 216. 



Isolepis sulcata, Carmicli. in Trans. Linn. Soc. Loud., xii. p. 503. 



Isolepis carmicliaelii, Dietr., Sp. PL, ii. p. 107. 



Scirpus thouarsii, Spreng., Syst. Veg. cur. post, p. 27. 



Scirpus conspersus, Bceckel. in Linnam, xxxvi. p. 505, pro parte i 



Tristan da Cunha Group. — Endemic? Thouars; Carmichael ; MacGiUivray ; 

 Moseley. 



This is perhaps the same as Scirpus inundatus, Spreng., as limited in Bentham's Flora 

 Australiensis, vii. p. 329, and the Isolepis prolifera, Hook, f., Fl. Tasm., ii. p. 87, t. 144 

 (but not of B. Br.), is scarcely distinguishable from our plant. 



Scirpus sulcatus, Thouars, var. moseleyanus, Hemsl. (Plate XXXII.) 



Scirpus sulcatus, Thouars, var. moseleyanus, Hemsl. 



Scirpus moseleyanus, Boeekeler in Flora, 1875, p. 262 (species). 



Nightingale and Inaccessible Islands. — Endemic. Moseley. 



At first sight this looks very different from typical Scirpus sulcatus, but after a careful 

 examination we can come to no other conclusion than that it is a form of the same species. 

 Among the specimens of undoubted Scirpms sulcatus from Tristan da Cunha, in Kew 

 Herbarium, is one about four inches high, and the tallest is about twenty-eight inches. 

 Between these extremes there is every gradation; and some of the plants collected by 



