Mr. J. Miers on the Genns Rhabdia. 433 



In regard to its real affinity, it is clear that the peculiar 

 placentation just described would remove it far from the Ehre- 

 tiacecBj tinder the supposition that the carpical structure of the 

 latter accorded with the rule that has been hitherto under- 

 stood : but it is quite otherwise ; for a more searching exami- 

 nation into the structure of Ehretia and its congeners has 

 revealed the fact, which I shall be able to demonstrate, that 

 there is little difference in their placentation from that of 

 Rhabdia and Cortesia. Consequently Rhabdia will still re- 

 main a member of this family. 



There is, however, a wide distinction between Ehretiaceoi 

 and BorraginacecB {Borragece of De Candolle), the latter of 

 which ought certainly to stand as a family distinct from all the 

 tribes associated with them in the ^ Prodromus,' because they 

 differ essentially in the peculiar gynobasic disposition of the 

 carpels. By adopting as a basis of arrangement the various 

 modes of organization of the carpels, the Hydroj)hyUaGece 

 would still occupy the place assigned to them by De Can- 

 dolle; but if we transpose the Polemoniacece^ Convolvulacecej 

 and Erycihem (all with an inferior radicle) to a more suitable 

 position, a more satisfactory arrangement will be attained. 

 The Ehretiacece osculate with the Borraginece^ and approach 

 the Heliotropiece in their distinct carpels and simple style. 

 Though it may be impossible to express the relative degrees 

 of affinity of these several groups in a lineal series, the follow- 

 ing would be a nearer approach to it than any hitherto pro- 

 posed. Thus we should have — Cyrtandracece^ Hydrophyl- 

 lacece^ Ehretiacece^ Borraginece^ Heliotrojpiacece^ Cordiacece^ ^ 

 Hydroleacece^ Erycibece^ Convolvulacecej Bolemioniacece^ Scro- 

 phulariacecej &c. In this manner the pentandrous hypogynous 

 Monopetalece with two or four carpellary ovaries and a supe- 

 rior radicle all fall into one continuous series, with more har- 

 monious steps of transition, while those with an inferior 

 radicle are made to follow. 



Rhabdia, Mart. ; — Ehretia in parte auct. — Sejjala 5, sub- 

 asqualia, lanceolata, persistentia, sestivatione imbricata. Co- 

 rolla subcampanulata, imo tubulosa, ad medium 5-loba, 

 lobis oblongis, subacutis vel rotundatis. Stamina 5, lobis 

 alterna, ad basin tubi inserta ; Jilamenta filiformia, tubo 

 longiora ; antherce ovatse, erectse, 2-loba3, lobis ovatis, col- 

 lateraliter adnatis, rima longitudinali introrsum dehiscenti- 

 bus. Discus minimus, glandulosus, simplex aut nullus. 

 Ovarium superum, conico-ovatum, septis 2 incomplctis e 



* In this interval should be placed a new family, the Auxemmacece, 

 which will be shortly described. 



