2 
imbricate.* The line would thus be drawn between Petunia and 
Salpiglossis, two genera closely allied in habit. In the first, how- 
ever, the decidedly plicate corolla and 5 stamina show it to be a true 
Solanea, whilst the slight irregularity of the corolla and the declinate 
very unequal stamina, indicate an approach to Salpiglossis, which, 
being always didynamous, with an imbricately aestivating, or ob- 
scurely plicate corolla, is a genuine Scrophularinea. 
In the tribe of Verbasceae the genus Verbascum, as being pentan- 
drous, and Celsia, because it cannot be separated from Verbascum, 
have usually been referred to Solaneae, although there are not in 
that tribe any plants nearly allied to them, but the aestivation of the 
corolla, besides the general habit, leave no doubt that Bartling and 
others are right in classing these genera among Scrophularineae. 
Of the other Personate orders those whose genera or species have 
been most frequently mistaken for, or considered as Scrophularineae, 
are : 1. the Gesnereae and Orobancheas, distinguished in particular by 
their unilocular ovarium, with parietal placentae, although the latter 
protrude sometimes after fecundation, so as to form a 2-4-locular 
fruit ; 2. the Bignoniacese, Cyrtandraceae and Pedalineae, which have 
exalbuminous seeds, besides which the two latter have an unilocular 
ovarium, with an unilocular, or spuriously 2-4-locular fruit. The 
above characters, although not always very easy to ascertain, appear, 
nevertheless, to be decided and constant, they are, moreover, accom- 
panied usually by differences in habit and other minor characters ; 
and I am acquainted with few, if any, intermediates. 
Gesnereae have usually a semi-adherentf ovarium, a character which, 
amongst Scrophularinea?, I have only observed in a slight de- 
gree in some Calceolariee ; and these have the regularly bilocular 
ovarium and fruit of the latter order. Any further details, however, 
respecting the character and affinities of Gesnerese are rendered use- 
less by the elaborate exposition by Martins, in his Nova Genera et 
Species, vol. 3. 
Orobanchea? are at once known by their peculiar habit. They 
appear to be always parasitical, are never green, and their leaves are 
converted into scales. The nearest approach to them amongst Scro- 
phularineae is to be found in the genus Buchnera, in which most, 
if not the whole, of the section Campyleia are parasitical, and the 
B. hydrabadensis is, like the Orobanchese, leafless, but with the 
ovarium and capsule of Buchnera. 
Bignoniacese are frequently arborescent, which is very rarely the 
case amongst Scrophularinese ; the same thing may be said of their 
pinnate leaves, long capsules, and winged seeds, but as each of these 
* See Dr. Lindley’s Observations in tbe Botanical Register, Vol. 19. fol. 1626. 
f The terms adherent and free, generally used by foreign Botanists, appear to me 
to be preferable to those of superior and inferior, more fi-equently adopted in this 
country. 
