MR. G. BENTHAM ON AFRICAN ANONACEiE. 473 



7. MoNODOUA, Dun. ; Bentli. et Hook. f. Gen. PI. 26. 



The genus Monodora, entirely African, is one of the most marked among Anonacese ; 

 for altliough placed in the tribe MitrephorecB, as having the outer petals spreading, with 

 the inner ones connivent over the genitalia, and contracted at the base as in liitrepliora 

 itself, with the normal anthers of the three first tribes of Anonacese, yet it is at once 

 known by the large undulating and variegated outer petals, united at the base with the 

 inner ones in a short ring as in Hexalobtis ; and the structure of the ovary is so peculiar, 

 that it has been often added only at the end of the order as an anomalous genus. In 

 my former notes on the Order (Journ. Linn. Soc. v. 72), I showed that the old idea of 

 the ovary being monocarpeUary, with the whole inner surface Mned with ovules, as in 

 the carpels of some Nymphseacese, was erroneous, and that the ovary consisted, in fact, 

 of a large number of carpels united into a single unilocular ovary with parietal placentas 

 as in some Papaveracese and in several regularly parietal Orders, but that these pla- 

 centas are so numerous as to be absolutely contiguous and as it were blended with 

 each other. This view has been disputed by Mr. B. Clarke, who, from the fact of the 

 stigma of Jf. myristica being frequently oblique and even split down on one side, argues 

 that it is evidently not a compound one, but the ordinary oblique stigma of a single 

 carpel. Its really compound nature, however, which had been already ascertained with- 

 out doubt by Dr. Hooker and myself in the M. termifolia, has been fuUy confirmed by 

 the examination of the species since discovered by our intrepid African collectors, in 

 which the stigma is still more distinctly lobed. The fruit also of 3£. gramUflora often 

 shows a number of external longitudinal ridges and furrows, indicating the backs and 

 sutures of the carpels ; and in a small-fruited species from the Zambesi, of which we 

 have unfortunately neither leaves nor flowers, the sutures of the carpels are distinctly 

 marked by prominent costae. 



We have now flowering specimens and fruits of four apparently perfectly distinct 

 species, and fruits only of two more, which, with the M. angolensis, Welw., which is 

 unknown to us, carry the number of species to seven. But there is considerable 

 difficulty in framing diagnoses so as to make it easy to recognize them. All are 

 perfectly glabrous, except a few tufts of hairs or partial pubescence on the inner petals ; 

 most of them shed their old leaves before the flowering-season, so that the flowers are 

 accompanied usually by young membranous half-grown leaves, which it is difficult to 

 compare with the full-grown more or less coriaceous and shining ones of the fruiting 

 specimens ; and in the case of two species, fruits alone were found on trees which had 

 lost all their leaves. The flowers also, as in many other Anonacese, are very different 

 in size and shape when they first expand and when they are fully developed. The most 

 tangible characters appear to be derivable from the shape of the inner petals, from the 

 position of the bract, and from the inflorescence on the old wood or on the young shoots. 

 Each species has likewise its own peculiar foliage, but variable within limits very 

 difficult to define. The fruits are also in most cases readily distinguishable from each 

 other in size, shape, or consistence. 



The arrangement of the seeds in the ripe fruit is very singular. In most of the species, 

 especially in M. grandiflom, the cavity is entirely filled by a large number of seeds fitted 



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