OF PLANTS CALLED COMPOSITE. 313 



flower and fruit, of both species of Boopis in flower, and 

 detached flowers and pericarpia of Calycera. In all of 

 these I have found the ovulum pendulous ; and in Acicarpha 

 and Calycera an inverted embryo occupying the axis of a 

 fleshy albumen. My conjectures, therefore, on their struc- ci36 

 ture and relation to Acicarpha spathidata of the preceding 

 paper, are completely verified by this examination, as well 

 as by the observations of M. Cassini, who with his usual 

 acuteness has detected the principal characters distinguish- 

 ing Boopidece from Compositse and Dipsaceae, between 

 which he has also placed them. 



As M. Cassini's Memoir, though read subsequently to 

 mine, is already published, the name Calycerece, which I 

 have proposed for this family, is superseded by that which 

 he has given it. 



But as his account of the order is by no means complete, 

 several characters of considerable, though not primary, im- 

 portance being entirely omitted, I may be allowed to add 

 to my paper some remarks on the more essential points of 

 resemblance and difference between it and the two families 

 to which it is most nearly related. 



The principal characters distinguishing Boopidece from 

 the whole of Composite are the pendulous ovulum and the 

 albumen inclosing the embryo, of which the radicle points 

 to the apex of the pericarpium. It appears to me necessary 

 to state all these characters, and nearly in the terms in 

 which they are here given : for, 1st, A pendulous ovulum 

 most frequently, indeed, is not, however, invariably con- 

 nected with radicula supera, though that direction of radicle 

 might here, as well as in Compositse, with confidence have 

 been inferred from the vascular structure of the ovulum. 1 

 2dly, Where the insertion of the ovulum is, as in this 

 family, evidently below the upper extremity, the radicle 



1 Some of the indications in many cases afforded by the structure of the uu- 

 impreguated ovulum, of the position and direction of the parts of the future 

 embryo, have hitherto been overlooked : the subject, however, for its elucida- 

 tion requires details incompatible with the limits of the present communication. 

 I have in another place (Flinders's Voyage to Terra Australis, ii. p. 601 

 [vol. i, p. 77]) thrown out a similarhint, which lias probably attracted no atten- 

 tion, and must reserve the explanation of both for a separate essay. 



