OAKESIA CONRADII. 11 



figure, and adopted the error. But any botanist may readily satisfy 

 himself, by examination, that the radicle in Empetrum lies next the 

 hilum, and points to the apex of the fruit;* thus invalidating 

 the character on which Don and Lindley rely for distinguishing 

 the family from Euphorbiacese. Since the other genera of this truly 

 natural group differ from Empetrum in really possessing an erect 

 seed and an inferior radicle, I may remark, in passing, that we 

 have here a case in point against the adoption of a rule recently 

 laid down by M. Ad. Brongniart, namely, that the direction of the 

 radicle is of much higher importance considered with respect to the 

 pericarp than with respect to the hilum.f 



The diagnosis of the genus Oakesia is stated by Klotzsch (I cite 

 from the translation by Mr. Tuckerman) as follows : — « We find 

 that Empetrum differs in having single axillary flowers supported by 

 three bracts, a three-leaved corolla, a 6-9-celled ovary sunk in a 

 fleshy disk, and a closely sessile radiately expanded 6-9-cIeft stig- 

 ma ; that Corema, agreeing with this plant in the habit and inflo- 

 rescence, is yet distinguished from it by the want of bracts, by a 

 three-leaved corolla, an ovary sunk in a fleshy disk, and a radiately 

 expanded six-cleft stigma supported by a short style ; and that Cera- 



* In no case have I found the embryo eccentric, as it is figured and described in 

 the Genera Fl. Germania, but always directly in the axis of the albumen, and with 

 a slight curvature corresponding to that of the seed. Neither is it so long as 

 there depicted ; being scarcely more than two thirds the length of the albumen. 

 It is in the work here referred to, that the compound pollen of Empetraceee has 

 alone been noticed ; but it is most strikingly seen in Oakesia. It is singular, now that 

 this group is so widely separated from Ericaceae (to which Jussieu appended Em- 

 petrum), that it should, after all, be found to accord with the Heath tribe in this 

 somewhat peculiar character. 



t Brongniart, Enumeration des Genres de Plantes culliv. au Mus. Hist. Nat. 

 Par., p. i,\. (introduction). 



