MEMOIR ON THE APOCYNACE.E. 



PRELIMINARY REMARKS. 



During my residence in Brazil, now many years ago, I had numerous opportunities 

 for studying many points of structure peculiar to this family, and of examining many 

 plants in detail, intending at a future time to descrihe several Brazilian species. 



This design, however, was superseded by the publication of Dr. MiiUer's admirable 

 monograph in the ' Elora Brasiliensis,' in 1860. But as many curious facts relative to 

 the organs of fertilization, and others concerning the structure of the seeds, were 

 observed by me, which do not appear to have come under the cognizance of that 

 botanist, I have been induced, at this late period, to take up the subject again, and to 

 embody my observations in this volume. 



The order, in the time of Jussieu, was little understood, when, in his ' Genera ' (1789), 

 he comprised in it all Asclepiadaceous plants. The celebrated Robert Brown, in 1811, 

 first separated them into two well-characterized distinct families * ; this memoir furnished 

 the materials for Endlicher's enumeration of the genera (1838). But we cannot appre- 

 ciate too highly the admirable monograph of this interesting family by Prof. A. De 

 Candolle, in his ' Prodromus ' (1844). We must bear in mind that the task of elaborating 

 the features of all the species in fuU detail was then too vast ; and we must regard the 

 enumeration of the host of heterogeneous "species under the heads of Taberncemontana 

 &ndi JEchites as an instalment of high value, as it furnished materials for work to be 

 afterwards completed. Dr. Muller followed this example, in describing under the same 

 heads a mass of Brazilian species ; but he did little to enable us to distinguish one species 

 from another. 



In order to promote this object, it appears to me necessary to classify and subdivide 

 the whole of them into uniform groups, each marked by pecuKar and easily recognized 

 characters. In aid of this design the present memoir is offered; but it is limited in its 

 range. 



* Mem. Wern. Soc. i. p. 12. 



