MR. W. FAWCETT ON А NEW SPECIES OF THONNINGIA. 243 
layer of cells surrounding the ovule is converted into an oblong thin putamen, consisting 
of sclerenchymatous cells, elongated at the sides, short at the apex and base, differing 
from those in the putamen of Langsdorffia in having the outer wall of the same thickness 
as the inner. Тһе seed fills the cavity of the putamen; the greater part of it consists of 
soft-walled parenchymatous cells. - 
“Тһе well-developed embryo is a noteworthy character; it is a nearly globose body, 
minutely cellular, with no distinction of parts. It is situated in the upper end of the 
seed, close to what may be assumed to be the position of the hilum, and is wholly 
immersed in the albumen. The only other genera of the order in which a similarly 
developed embryo has been detected are Cynomorium, Mystropetalon, and Corynea. In 
all the rest, in so far as at present described, the embryo is of a character wholly diffe- 
rent from the above, and is most inconspicuous, composed of a few very large, loose, 
transparent cells attached to a suspensor, only to be discovered by making most delicate 
sections, whereas in the genera named above, though minute, there is no difficulty in 
discovering the embryo, when present, by tearing open the albumen, when it can be 
turned out entire by the point of a needle. I have said ‘when present,’ because 
Weddell found the fully-formed embryo to be of rare occurrence in Sarcophyte*, and I 
have only twice seen it in Corynea, after dissecting a multitude of fruits. Eichler, 
indeed, states that the fruit of Corynea is unknown t, probably by oversight, as I have 
fully described it.” | 
The structure of the ovule agrees with Eichler's description and figure of Langs- 
dorffiat. The embryo-sac is long, with a large oosphere just below Ше apex, and a 
protoplasmic mass sometimes filling тар the space between the apex and the oosphere, 
probably representing the synergidz. In some instances a very large nucleus was seen 
at some distance below the apex, whieh is doubtless the first cell of the endosperm. 
Between the apex of the embryo-sae and the base of the style there are many long 
narrow cells, forming a conducting tissue. There are two or three layers of small cells 
immediately surrounding the embryo sac, corresponding in form and position with those 
which Eichler considers to belong to the ovule, while the cells of the ovary lying outside 
are long and narrow. 
The description of T. malagasica, as given above, modifies the character of the genus, 
as described by Bentham and Hooker §, bringing it very close to Langsdorffia. The 
following is the revised character :— 
THoNNINGIA, Vahl. Spadices unisexuales. Flores dioici. Fl. 4: Perianthium e squa- 
mulis 2-3 minutis lineari-subulatis, pedicello sparsis; aut regulare triphyllum, 
phyllis 3 lanceolatis; antherz 3-(5?), lineari-elongate, in columnam pedicello 
continuam connate, 2-loculares, loculis 2-locellatis extrorsum dehiscentibus ; pollen 
subglobosum. Fl. 9: Ovarium elongatum, anguste cylindraceum, basi interdum 
tumidum, cum vicinis totum coalitum aut liberum, vertice in marginem tubulosum 
* Trans. Linn. Soc. p. 54 (in nota). 
+ Eichler in DC. Prodr. xvii. p. 137. 
+ Fl. Bras. fasc. 47. Balanophoree, p. 19, tab. 3. fig. 14. 
§ Benth. & Hook. 4. Genera Plantarum, iii. p. 236. 
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