Ckeeseman. — Notice of the Occurrence of Hydatella. 433 



Carex pxjrenaica, Wahl. BuUer Valley ; T. F. C'heeseman. 

 echinata. Murr. Buller Valley ; T. F. Cheeseman. 

 ,, hreviculmis, R. Bt. Buller Valley ; T. F. Cheeseman. 

 Agrostis muscosa, T. Kirk. Buller Valley ; T. F. Cheeseman. 

 Hymenophyllum villosum, Col. Buller Valley ; T. F. Cheeseman. 

 ,, cheesemanii, Bak. ex Hook, and Bank. Wai- 



mangaroa : Dr. Gaze. 

 Alsophila colensoi. Hook. f. Serjeant's Hill : Mr. Green. 

 Lomaria dura, Moore. Waimangaroa Gorge : Mr. Wright. 

 Hypolepis millefo/ium. Hook. Buller Valley; T. F. Cheese- 

 man. 

 Lycopodium selago, L. Buller Valley ; T. F. Cheeseman. 



Art. XXXVI. — Notice of the Occurrence of Hydatella, a Genus 

 new to the Neic Zealand Flora. 



By T. F. Cheeseman, F.L.S. 



[Mead before the Auckland iiiditide, 3rd October, 190(J.] 



In the " Manual of the New Zealand Flora " (p. 756) I have 

 provisionally described, under the name of " Trithuria incon- 

 .spicua,''' a curious little plant collected by Messrs. H. Carse and 

 R. H. Matthews at Lake Ngatu, near Ahipara. As mentioned 

 in the Manual, the plant differs in several respects from Trithuria, 

 but my specimens were not sufficiently complete to justify me 

 in treating the species as the type of a new genus. 



A few months ago, through the kindness of Dr. Diels, I 

 received a copy of the " Fragmenta Phvtographise Australiae 

 Occidentalis," an important publication devoted to an account 

 of the plants collected or observed by Drs. Diels and Pritzel in 

 West Australia in the years 1900 and 1901. On turning to the 

 CentrolepidacecF I was much interested in finding the description 

 of a genus, for which the name Hydatella was proposed, which 

 evidently included the Lake Ngatu plant. Dr. Diels remarks 

 that the genus is allied to Juncella, F. Muell. {Trithuria, Hook. f.). 

 but differs in the inflorescence being monoecious, in the stipitate 

 flowers, in the longer and more numerous styles, and in the 

 bracts being usually two only : to which may be added that the 

 ovaries are neither angled nor compressed. Two species are 

 described, H. austral is and //. leptogyne, the first of which is 

 excellently figured. 



Shortly after the sheets containing the Centrole pidacecE of the 

 Manual had passed through the Press further specimens of the 



