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An Account of a New (jfenus of Plants called Diplogenea. 

 By John Lindley, Esq., F.R.S., Professor of Botany in the 

 University of London. 



The genus which is the subject of the following observations 

 forms part of a small collection of plants gathered in Mada- 

 gascar, for the Horticultural Society of London, by the late 

 Mr. John Forbes. By permission of the Society it has been 

 allowed to be described and made public in this Journal. 



The specimens consist of a few shrivelled branches 

 with flower-buds and expanded flowers, but without fruit. 

 From their appearance, it may be presumed that the plant 

 to which they belonged was parasitical. The branches 

 are brown, taper, fleshy, glabrous, very zigzag in direction, 

 when young compressed, with a few dichotomous ramifi- 

 cations ; the joints seem to have been rather tumid. The 

 leaves are opposite, fleshy, spreading, glabrous, entire, oblong, 

 retuse, tapering into a short petiole, triply ribbed, but other- 

 wise destitute of all appearance of veins ; their parenchyma, 

 consist of large irregularly hexagonal cells, many of which 

 are evidently filled with an oily fluid. The flowers are 

 small, and appear in very short, axillary, fascicled racemes ; 

 their colour has probably been white. The calyx is fleshy and 

 superior, with the limb falling off" like a lid, and leaving a sue- 

 culent dilated border behind ; it adheres firmly to the ovarium 

 on all sides, and when the lid has fallen, which happens at an 

 early stage, resembles a truncated calyx ; the coat of the tube 

 distinctly abounds with receptacles of oil. The petals are four, 

 lanceolate, acuminate, fleshy, involute at the apex, and hav- 

 ing a twisted aestivation ; they are inserted on the outside of a 

 flat or concave fleshy disk, which occupies the summit of the 

 ovarium. The stamens are eight, inserted in a single row on 

 the outside of this same disk ; their filaments are ligulate ; 

 their anthers in aestivation inflexed, ovate, acute, with two 

 parallel cells communicating by a single pore at the apex, and 

 having at their base two subulate, falcate spurs, or appendages; 

 when the flower is expanded, the anthers acquire an erect po- 

 sition, and their lobes, which were before turned outwards, have 

 an inward direction, The ovarium is inseparably connected 



