CONTRIBUTIONS TO BOTANY. 
215 
responding strip of the staminal tube is torn away to the 
base, and the petals are thus left quite free : this tube is too 
delicate and membranaceous to be detached in an entire state 
without laceration ; but the structure, by the treatment I have 
mentioned, is thus rendered manifest. All the parts of the 
flower are isometrical in number, and symmetrically arranged : 
five free linear sepals rise from the hemispherical cup of the 
calyx ; five alternate petals spring from the margin of the cupular 
disk, which is adnate to this cup ; and ten anthers in one regular 
series are disposed on the summit of the adnate tube formed of 
the confluent filaments, five being alternate and five opposite 
to the petals, so that they thus appear sessile in the mouth of 
the seemingly gamopetalous tube of the corolla. The structure 
of these anthers offers a striking peculiarity : they are renifonn, 
compressed, erect, affixed by their basal sinus upon a very short 
and broad portion of the filaments, which are conjoined below 
into a monadelphous adnate tube, as before mentioned : these 
anthers consist of two collatei’al cells, united into a compact 
body ; and they open a httle obliquely by a lateral fissure, or 
rather by a hippocrepial line round their margin, into two un- 
equal valves, the posterior retaining its naturally erect position, 
the anterior valve becoming bent downwards. If we compare 
this structure with the stamens of Biittneria, we perceive a close 
similarity between them, — the chief difference being that in the 
latter case the monadelphous tube of the stamens is free from 
the corolla down to its base, the union of the filaments is there 
not complete, and the free portions of the filaments appear as so 
many segments of the border of the tube. Gay, in his mono- 
graph of the family of the Biittneriacea, shows that in Commer- 
sonia Fraseri* five of these stamens are anantherous, much 
extended, and 3-fid, and five alternately short and antheriferous ; 
its anthers are reniform, like those of Diclidanthera, and are 
fixed by their sinus to the apex of the short broad filament, 
which is reflexed at its apex, and the stamens appear as if they 
were extrorse ; each anther, in like manner, opens by a hippo- 
crepial line bilabiately, the internal valve remaining pendent, 
and the more external valve rising into a vertical position, so 
that the anther thus expanded is peltate, its cells being colla- 
terally placed. If we imagine the monadelphous tube in this 
case, as well as its free segments, to be agglutinated to the 
corolla, as in Diclidanthera, the anthers would necessarily be 
erect, instead of reflexed, we should find them placed exactly as 
in that genus, and their dehiscence would be precisely similar. 
The ovary is globular, decidedly stipitate, as in Biittneria, 
* Mem. du Mus. x. p. 215. tab. 15. figs. 8, 9, 10, & 11. 
