CONTRIBUTIONS TO BOTANY. 
33 
times exhibits two or three ovules, as I have distinctly seen in 
O. amentacea. This fact was evidently more than suspected by 
Mr. Bentham, who says [loc. cit. p. 674) that it appeared to him 
there were two ovules in Opilia, three or four in Cansjera, a cir- 
cumstance rendered juobable by the evidently compound nature 
of the stigma in both genera, but which on account of the ex- 
cessive minuteness of the parts he could not ascertain from dried 
specimens : after fecundation he never found traces of more than 
one ovule. The order however will admit of being divided into 
tribes, by some of the characters already indicated, but in a sub- 
sequent memoir I will offer my views on this subject. 
As I shall have shortly to treat of Leretia, and other correla- 
tive genera, I shall be able to detail at greater length the nume- 
rous observations that have induced me to propose the separation 
of Mr. Bentham’s tribe Icacinea from the Olacacece ; it will at 
present be sufficient to state, that they constantly differ in having 
the stamens alternate \rtth, not opposite to the petals ; they always 
want the hypogynous disk that forms so frequent and so remark- 
able a feature in that family, although they sometimes exhibit a 
similar epigynous gland upon a superior ovarium ; they differ 
also most essentially in the stnicture of their somewhat gibbous 
ovarium, which normally will be seen to be 5 -celled, but which 
with a single exception is by abortion always completely uni- 
locular, and without the smallest indication of any free central 
placenta, the ovules being generally two in number, attached 
somewhat laterally, from near the summit of the cell. The 
fruit differs most essentially in structure from that of the 0/a- 
cacete, being a drupe, enclosing a single nut, with a solitary 
albuminous seed, that is covered with the usual testa and inner 
integumental envelopes, and distinguished by a well-marked 
chalaza and raphe, which, as in Euonymus, is averse or dorsal 
in respect to the axis of placentation. This is very manifest in 
Pennantia, a genus clearly belonging to this family. 
In a former page {ante p. 29), while speaking of Villaresia and 
Bur simpet alum, genera belonging to Aquifoliacece, I pointed out 
the existence of the identity of structure of the ovarium in those 
genera with that of the Icacinea, and I stated many other cir- 
cumstances, tending to prove how closely this tribe is related to 
that family, and that its affinity with the Olacacece is in reality 
very distant. This very different structure of the ovarium did 
not escape the penetration of Mr. Bentham, but as he had not 
observed the constant, essential, and dissimilar points of floral 
structure, as above described, he states in the memoir before 
cited, that he did not consider the single fact noticed by him to 
be a sufficient reason for separating the Icacinece from the Ola- 
cacece. It is evident however, from the many circumstances 
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VOL. I. 
