including a new Arrangement of Phanero^mohis Plants. 457 



anterior, of which an instance occurs in the nearly allied Bakia, 

 as shown by the parietal placentation of the two ovules. fPl XV 

 figs. 14 & J 5.) 



BRTjNiACEiE. In Brunia lanuginosa the ovary consists of a 

 single carpel always anterior. (PI. XV. figs. 16, 17 & 18.) 



Umbelliferje. The position of the odd carpel is perhaps in 

 some cases variable, but in yEtkusa Cynapium the anterior carpel 

 IS much more frequently fertile, which may arise from the pos- 

 terior one being occasionally smaller ; the carpels are very com- 

 monly all anterior and posterior, but this is not without excep- 

 tion, the anterior and posterior position however still predomi- 

 nating as in Araliacese. 



Casuarinal Exogens. 



The families derived more immediately from Gymnosperms 

 through Casuarina difi"er, as far as is at present known, from other 

 divisions of Exogens, in having the raphe in pendulous ovules 

 always next the placenta, a character which becomes less frequent 

 as Endogens are approached. The connexion between the ape- 

 talous and polypetalous forms of this section is sufficiently ob- 

 vious and has been frequently referred to ; but the affinities be- 

 tween the polypetalous and monopetalous forms are not of so 

 decided a character. It may be observed, however, that in their 

 coronet Asclepiadese may be compared to Passifloracese ; that 

 they have in some instances the habit of Euphorbiaceffi; and that 

 Rauwolfia among Apocynacese is an approach both in structure 

 and habit to the latter family. And Apocynacese may also be 

 compared with Violacese in their crested anthers. 



AscLEPiADEiE and ApocYNACEiE. In such genera of these 

 families as I have examined, the raphe (in cases of ovules nume- 

 rous and horizontal) is always on the under surface of the ovule, 

 which occasions the seed in Gomphocarpus, having become de- 

 pressed in subsequent growth, to be pendulous with the raphe next 

 the placenta, and the ovules oi Liquidambar have I believe an 

 equivalent character, the only other instance of the kind when 

 numerous I have met with. In Rauwolfia the ovules are two, 

 pendulous, with the raphe next the placenta, the raphe becoming 

 rather curved as it descends, as in Roumea. 



EuPHORBiACE^. When my first Dissertation on the Position 

 of the Carpels was read to the Linnsean Society, Eremocarpus 

 was considered to have its single carpel variable, although it re- 

 mained a question whether it was not sometimes posterior; but 

 having more recently examined that genus, I ascertained that in 

 upwards of fifty instances there were no carpels posterior, and it 

 was doubtful if any were lateral. The inflorescence here consists 



Ann. i^ Mag. N. Hist. Ser. 2. Vol.xi. 30 



