236 
CONTRIBUTIONS TO BOTANY. 
pyle is placed over the fascicle of stigmatic tissue, evidently in 
its normal and proper position. Another confirmation of the 
same view occurs in Rhamnus Alaternus, where, in the ripe seed, 
the raphe is exactly dorsal, as in R. catharticus : here I found 
the unimpregnated ovule having its raphe precisely in the same 
position as in the seed, with its micropyle placed over the im- 
pregnating point of the placenta, and situated between the funicle 
and the axis of the ovary, proving that in this case there had 
been no twisting of the funicle, and consequently no pivoting of 
the ovule. I have also examined the living ovary of Rhamnus 
catharticus in an extremely young state, long before the ripen- 
ing of the anthers, and therefore prior to its impregnation, and 
1 have found the raphe most distinctly upon the dorsal face, 
precisely in the same position which it occupies in the ripe seed. 
All the evidence that I have thus been able to collect tends 
therefore to subvert Mr. Bennett’s hypothesis. On the other 
hand, the explanation I have offered on a former occasion *, of 
the cause of a dorsal or lateral raphe occurring, as I believe it 
does, universally throughout the Rhamnacees, appears to me 
quite satisfactory : here, from a most simple and natural cause, 
originating either in the epipylar or allopylar pullulation of the 
nascent development from the basal placenta, we have the ovule 
either with a dorsal or lateral raphe j and, where dorsal, it is 
forced into that averse position by the mere act of the resupina- 
tion of the ovule owing to the pressure of its growth against the 
base of the cell, in the manner first sagaciously suggested by 
Mr. Brown in the case of Euonymus. Had the same epipylar 
pullulation originated out of a higher point of the axis of the 
ovary, we should have seen in that case a pendent ovule with a 
ventral raphe, as occurs in the neighbouring family of the Celas- 
tracece, where in the same cell, from the cause here assigned, we 
sometimes meet with ovules, some with a ventral and others 
with a dorsal raphe. 
I will now advert to the other anomalous fact, in regard to 
the raphe, above 'alluded to. Botanists have always attributed 
to the seed of Rhamnus a chartaceous testa, with a raphe as a 
simple cord, that runs up its external face, or along one side, in 
a deep groove formed by a conduplicature of the whole seed, 
and then terminates in the apical chalaza; but one important 
circumstance connected with this structure has been altogether 
overlooked. I have found that this cord has a peripherical 
range similar to that* in Colletia, with this difference, that in- 
stead of running laterally round it in the line of the margins of 
the cotyledons, it is directed along the middle of one cotyledon, 
* Huj. op. p. 210 ; Ann. Nat. Hist. 3 ser. iv. 25. 
