90 
Hooker. — On Hydrothrix , 
sessiles ; spatha propria tenuissima , hyalina , basi v. medio 
pedunculi inserta , folio s tip at a ^ primum ovoidea clausa , demum 
apice rupta tnmcata v. lacera ; bracteae oblongae , obtusae , 
hyalin ae, valvatim cohaerentes , canalibus resiniferis interruption 
striolatae. Perianthium infra medium 6-fidum, lobis linearibus 
obtusis , majoribus 3-nerviis , minor ibus \-nerviis. Stylus ala- 
bastro supra medium deflexum , stigmate anther ae applicito. 
H. Gardneri, Hook. f. (Tab. vii). 
Hab. Brasilia tropics, prov. Ceara ; in alveo arenoso 
fluvii Rio Sulgado dicti, inter Ico et Crato. Gardner , Aug. 
1838 (No. 1863). 
This remarkable plant has lain buried for just half a century 
in the many herbaria which possess Gardner’s collections, and 
probably in all, under the category of ‘Plantae dubiae affinitatis.’ 
Though the Kew specimens had been submitted to various 
botanists, its relations were not recognized until the analyses 
which accompanied it in the Herbarium at Kew were shown to 
Professor Asa Gray, who suggested a comparison with the North 
American Schollera graminea 1 * * * . Following up this suggestion 
for the purpose of preparing an account of the plant for the 
Annals, I find ample confirmation of this view ; for though 
in all respects of habit, foliage, inflorescence and flowers, it is 
totally unlike any known genus of Pontederiaceae, it is un- 
questionably a member of that order ; and a reference to the 
Conspectus of the Monocotyledonous families in the ‘ Genera 
Plantarum 5 shows that, in respect of diagnostic characters, it 
can belong to no other. It is evidently a flaccid annual, 
growing deeply rooted in the sand by its mass of capillary 
fibres, and by branching repeatedly from the base and upwards 
forming patches of considerable extent five to eight inches 
high. The stems are about J in. in diameter, and the filiform 
leaves J to 1 in. long by in* broad in the middle. The 
1 A. Gray, Man. Bot. North. United States, 483 (syn. Leptanthus gramineus , 
Michaux, FI. Bor. Am. i. 25, t. 5, f. 2; Hook. Exot. Flor. t. 94). Schollera is 
now reduced to Heteranthera , Ruiz, et Pav. (Gen. Plant, iii. 839 ; Solms-Laub. 
in A. De Candolle, Monog. Phanerog. iv. 517)- 
