246 BOTANICAL- INFORMATION. 
whilst in the lower part it is two-celled only. This I have 
observed in.several species of Choisy’s Batatas, and he him- 
self admits it in Calonyction. That, the absence of the dissepi- 
ment between the carpels in some convolvulaceous fruits is 
of no greater importance, is proved by Alphonse de Candolle, 
who (in a note, p. 463 of the same vol.) states that the sup- 
posed unilocular ovary of Porana and Shutereia at least, is in 
fact bilocular. 
The only real difference.with regard to the ovary lies in 
Pharbitis, where there is an additional carpel with its two 
ovules, and sometimes it would appear, two additional ones. 
Whether or not this character be found sufficiently constant 
_to retain the genus (for it is variable in some species), it can- 
not at any rate be placed in the same category as the deve- 
lopment of a spurious dissepiment between the seeds. 
Attaching, however, no more than generic importance to 
all these modifications, and considering it necessary to adopt 
them, if not as natural, at any rate as artificial distinctions, in 
so very numerous a group of species, they may be useful or 
even the most useful, provided (in the absence of all vege- 
_ tative characters), they really exist in the species supposed to 
possess them; but even in the few Convolvulacee we have 
‘had leisure to compare, we have found several (and those well 
known to the author by specimens or good figures), arranged 
in genera from whose character they completely differ. Thus: 
Ipomea muricata, Roxb., a common East Indian plant, has 
a corolla nearly the shape of that of the common Pharbitis 
purpurea, with stamens shorter than the tube; we find it in 
Calonyction, of which the character is * Corolla infundibuli- 
formis (which is not incorrect), stamina exserta,” and more- 
over reduced as a synonym to the Jp. bona nox of Linnaeus, 
where the corolla is twice the size and almost hypocrateriform, 
with the stamens really exserted. . 
Ipomea longifolia, well figured in the Botanical Register, à 
species found in the elevated regions of the interior of 
Mexico, having a two-celled fruit, without any trace of trans- 
verse dissepiments, as shown in. the figure, is placed in 
