ILLUSTRATIONS OF INDIAN BOTANY. 25 



sc^cey be confounded with any other, except perhaps Pa..,>,r^, there is not one where the 

 difliculty of assigning definite limits to either genera or species is more felt. 

 ^ Deferring to their proper place, all remarks on the genera and organs from which the charac 

 ters are taken, I may observe here, that the discrimination of the species is most difficult, as no 

 dependence can be placed on the form of the foliage as affording specific characters, almost every 

 variation of form from simple, up to much divided leaves, being found in the same species 

 and even occasiona lly on the same plant. Nearly all are annuals, with climbing succulent stems 

 furnished with tendrils, supposed to be abortive lateral stipules, or according to modun liotani- 

 cal doctrines transformed leaves, stipules being considered modified leaves. The flowers are 

 usually unisexual, the male and female generally on the same plant or even sprinc^ing from the 

 sameaxi ; more rarely they are on different plants as in the exauiple given, f frlchomnthu^ 

 palmata) usually the flowers are white, red or yellow. The coloured portion of the flower is 

 supposed by some Lotanisfs to be a petaloid calyx, and the apparent calyx, merely certain 

 externa! appendages, a view not likely to find many proselytes. The stamens in this order are 

 peculiar and present many variations of form. These have recently been employed to sunplr 

 sectional characters for the distribution and more easy definition of genera. The fiuit like every 

 other part of these singular plants, is quite sui geiierh and is in consequence designated by its 

 own name, Pepo or pepomda, whence Pepomferce the name given by Hartling and Endlicher 

 to the class. A true pepo is, as I have recently shown, TMadras Journal of Science) a tri-car- 

 pillary fruit^but wilh the carpels inverted : that is with the dorsum of the carpellary leaf in the 

 axis, and the placentiferous margins turned towards the circumference ; instead of as usual 

 with other fruits, towards the axis. Differences so great, in the construction of 'this most 

 essential organ, mark this as a peculiar order, the affinities of which have still to be discovered 

 ^ These rather extended introductory remarks I have felt to be necessary to facihtate the 

 right understanding of this very difficult and curious order. 



"Calyx .5- toothed, sometimes obsolete. Petals 5, distinct or more or less united, sometimes 

 scarcely distinguisha!)le from the calyx, strongly marked with reticulating veins, sometimes 

 fringed. Stamens 5, distinct or triadelphous : anthers 2-celled Tor rarely 1-celled), usually lone 

 and sinuous, rarely ovate. Ovarium adhering to the tube of the calyx, of 2 or 3 carpels. Car- 

 pels inverted, thai is, having the dorsum in the axis and placentiferous margins in the circum- 

 ference, hence the fruit 2-3 celled but with 4 or 6 parietal placentas ! ovules solitary or indefinite 

 imbedded in pulp: style short ; stigmas 2 or 3,2-lobed, very thick, velvety or fringed Fru * 



fleshy, usually a peponida. Seeds usually ovate and compressed, enveloped in a juicy or dry 

 and membranous, arillus : testa coriaceous, often thick at the margin. Albumen, none Embryo 

 straight : radicle next the hilum : cotyledons foliaceous, palmatinerved. Stem succulent • 

 climbing by means of tendrils usually lateral, and formed of abortive stipules. Leaves palma- 

 tinerved, alternate. Flowers unisexual" 



Affinities. These are not by any means clearly understood. Hitherto CwcM/izVaceafi 

 have been, by the almost universal consent of Botanists, arranged among orders with one-celled 

 ovaria and parietal placentas, a place they can no longer be allowed to occupy if the above ex- 

 planation of the formation of a pepo be found correct, since in it, we have a peculiarity of struc- 

 ture by which this family is widely separated from every other known order of the vegetable 

 kingdom. Lindley places them in his Epigynous group, among a suit of orders all having a cen- 



e, but distinguishing the Cucurbitat alliance by the character " Placentse parietal" 



tral placentae 



and remarks, in another place 



id. 



except in their sinuous stamens, unisexual flowers and exalbuminous seed." Endlicher places 

 them between two parietal groups, associating with them another very curious fandly, BeToni- 

 aceoe, the affinities of which, if his view is correct, must up to this time have been totally misun- 

 derstood. 1 he very intimate union of the calyx and corolla, which led Jussieu to view the flow- 

 er as apefalous, and range the order under his class Apetala-, is a point of structure which can- 

 not he overlooked in determining its affinities ; for, though I think Jussieu's view on this point 

 essentially incorrect, yet, it has had the effect of pointing out a relationship with Euphorbiaceae 



in some points striking, but which might otherwise have been overlooked. As an order the Cu- 



