_ AFFINITIES OF BALANOPHOREÆ. 17 
appear minutely wrinkled on the surface. The long single style of Mystropetalon termi- 
nates in a clavate or capitate, and evidently 3-lobed stigma. Sarcophyte has a sessile, 
broad, discoid stigma. The style of Cynomorium is more complex than in any other 
species, and terminates in a 2-lobed stigma; it is provided with two vascular cords and a 
central groove occupied by stigmatic tissue :—a detailed account of it will be found in the 
remarks upon C. coceineum. : 
In all the above-mentioned plants the cellular tissue of the ovary is very loose, consist- 
ing of oblong utricles, usually furnished with cytoblasts, and without any vascular tissue 
in its walls (except in the style of Cynomorium) : there is, however, a manifest approach 
to vascular tissue in the woody cells of the superior perianth of Thonningia, and perhaps 
also of Langsdorffia. 
Ovule.—This is invariably solitary, and pendulous from the summit of the cavity of the - 
ovary. In both Monostyli and Distyli its insertion is so near the very centre of the cavity, 
that I cannot detect any deviation in its position from the axis of the ovary; nor in the 
Distyli do I find it to be placed nearer to one of the styles than to the other. 
The earliest appearance of the ovule of Balanophora is as a solitary cell, protruded from 
the wall of the ovary: its subsequent stages I have followed to some extent in B. involu- 
erata, though, owing to the rapid sphacelation of the cellular tissue of the ovary imme- 
diately after opening it, and the extreme minuteness of all the parts, the analysis is one of 
great delicacy, and proportionately liable to error. 
Plate V. figs. 11 & 12. represent an opened ovary of B. involucrata, showing a very 
young ovule, consisting of a delicate hyaline sac suspended almost immediately below the 
insertion of the style, and containing two free spherical cells, each full of fluid and covered 
with opaque spots, which are probably cytoblasts. I found it impossible to detach the 
ovule, or to view it, except im situ, and by transmitted light. The formation of cells pro- 
ceeds with great rapidity within the sac, but I was unable to trace their evolution. The 
resemblance between the cells thus developed, and those in the embryo-sac of ordinary 
ovules, is obvious, and it suggests the possibility of the ovule being reduced to an embryo- 
sac. I could obtain no clue to the period at which impregnation is effected, nor to the 
particular action of the pollen-tubes, which I never found within the cavity of the ovary 
or ovule* : nor could I trace on any part of the surface of the ovule, any indication of a 
chalaza, raphe, or foramen, at which impregnation is probably effected. After the ovule . 
has swelled, so as to fill the cavity of the ovary, it adheres by means of its membranous 
coat to the walls of the ovary ; at which time it consists of a dense opaque mass of 
eohering hexagonal cells. 
. "The ovule, as thus described, does not materially differ from that of Viscum, as described 
in Decaisne’s admirable memoir on that plant (Mémoires de l’Académie de Bruxelles), 
except in being more simple; the ovule of Viscum consisting of an embryo-sac covered by a 
delicate cellular membrane (the tercine of Mirbel), and the greater portion of the substance - 
of its nucleus being undeveloped. Regarding Balanophora as presenting the most reduced 
form of ovule, Loranthacee are a step higher, and from these the passage is direct to the 
. naked nuclei of Santalacee and their allies, of Cornea, Caprifoliaceæ, Rubiacee, Umbelli- 
* But which M. Hofmeister has observed in the ovule itself of Cynomorium. . 
VOL. XXII. D 
