[ 463 ] 

 XXX. On African Anonacese. By GEORaE Bentham, Esq., Fres. L.S. 



Read April 17th, 1862. 



J^NONA CUJE, although evidently numerous in tropical Africa, are amongst the least- 

 known of the plants of that continent. In the ' Niger Flora,' published in 1849, Dr. 

 Hooker indicated twenty species as then more or less known ; but that number included 

 three cultivated Anonas, and two or three supposed species since ascertained to be mere 

 synonyms ; and very few have since been published. They are generally trees or woody 

 climbers, bearing but few flowers, little attractive to the eye, and having considerable 

 external resemblance to each other. The specimens gathered by collectors are there- 

 fore generally few and imperfect, often with only a single flower which cannot be 

 examined without destroying the specimen, and yet the changes in form which the parts 

 of the flower undergo in the course of their development would often require their 

 examination in bud and in the full-grown flower, as well as in fruit, before their generic 

 and specific afiinities can be ascertained with precision. At the time of preparing the 

 Order for our 'Genera Plantarum,' our African materials were still very deficient; many 

 valuable additions were, however, received from the late Mr. Barter in time for the 

 revision of our manuscript before going to press : but those more recently transmitted 

 by Mr. Mann from the West Coast, and by Dr. Kirk from the Zambesi, could only be 

 alluded to whilst correcting the last revise ; and some have only come to hand since the 

 sheet was printed off. Having now examined them all, it has appeared to me that some 

 were of sufiicient interest for figuring in the ' Transactions ' of the Society, and I have 

 accordingly accompanied the plates I have had prepared by a synopsis of all the African 

 species contained in the Kew herbaria in so far as the specimens permitted ; and I have 

 also enumerated the few published species which I have been finable to identify, as well 

 as such new ones as, from the imperfection of the specimens, must remain as yet of 

 doubtful affinity. 



AnonacecB, with few exceptions, have a very limited geographical range. Their 

 usually arboreous habit, slow growth, tardy maturity, and comparatively few flowers 

 with indehiscent fruits, little attractive to birds and not endowed with any peculiar 

 means of dispersion, give to most of the species but few chances in the general 

 struggle for existence. Of the nearly forty African species now more or less known, 

 all are confined to that contiaent, with the exception of the American Anona palus- 

 tris, which appears to be really native in the swamps of the western tropical coasts ; 

 and none are as yet known to extend across from the West to the East, excepting 

 Anona senegalensis, which is, again, a very American form and very closely allied to 

 several American species. In Africa, however, it is described as covering immense 

 tracts of country in the greatest abundance, as well by Leprieur in Senegambia, as by 

 E. Vogel in Bornou and by Kirk on the Zambesi. 



Of eleven African genera, three, Sexalobus, Ilonodora, and Clatlirospermnm, all very 



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