260 Mr. J. Miers on the Menispermacese. 



16. Lecidea Dufourei, Ach. 



Est nomen in herbariis variis obvium Lichenis, quern Lecideam 

 sabuletorum, f. simpliciorem, dixi in Lich. Scand. p. 205. No- 

 men Acharianum restituendum. 



Etiam in Gallia occurrit, in Vogesis (Mougeot) ; atque in 

 Anglia (Leighton). 



XXXII. — On the Menispei-macese. 

 By John Miers, F.R.S., F.L.S., &c. 



[Concluded from p. 175.] 



60. Desmonema. 



This genus is proposed for a plant from Natal, with cordate, 

 deltoidly orbicular, submembranaceous, glabrous, 5 -nerved 

 leaves, the nerves branching externally, the petiole being long 

 and slender. It has an axillary inflorescence, with a somewhat 

 slender rachis as long as, or longer than, the leaves, the whole 

 plant so much resembling a species of Tinospora that it might 

 easily be mistaken for one. The inflorescence is a simple ra- 

 ceme, its rachis being provided at short intervals with a subu- 

 late bracteole, half the length of the 1 -flowered pedicel which 

 emanates from the same point; the flower has six sepals, which 

 are ovate, subacute, the three outer being alternate with and 

 half the length of the three interior ; six petals in two series, 

 the outer ones subcuneately ovate, three-quarters of the length 

 of the inner sepals, plane, the three inner ones a ti'ifle shorter, 

 linear, one-third their breadth, fuscous, subfleshy, longitudinally 

 canaliculated ; three monadelphous stamens as long as the outer 

 petals, the filaments being united for three-quarters of their 

 length into a central column, the upper extremities being free, 

 nearly erect, supporting as many subglobular anthers, which 

 are broader than them, 2-celled, the oval cells collateral, without 

 intervening connective, each cell opening bivalvately by a some- 

 what lateral and subextrorse longitudinal furrow. Desmonema, 

 in the feature of its three monadelphous stamens, resembles 

 Rhaptonema, Syrrhonema, Detandra, and Sarcopetalum. It dif- 

 fers from the first in its subextrorse anthers, in the number and 

 shape of its sepals, the kind of inflorescence, the form and vena- 

 tion of its leaves, and its very dissimilar habit. Syrrhonema 

 difi"ers from it in its introrse 4-lobed anthers, the want of petals, 

 the greater number of its sepals, and in the character of its in- 

 florescence. Detandra is distinct from it in its anther-cells, a 

 far greater number of sepals, the character of its inflorescence, 

 its peltate leaves, with another kind of venation. Sarcopetalum 



