244 MR. MIERS ON THE STRUCTURE OF THE SEED 



the aperture in the extremity of the testa, the whole nucleus forming, in his own peculiar 

 technology, " an epispermic antitropal embryo." There is, however, one essential error 

 in this otherwise correct description ; like other botanists, he has mistaken the base for 

 the apex of the seed. 



Jussieu, in 1813, in a memoir upon the characters of the Hypericinoe and Guttifera, 

 drawn from the structure of their seeds*, observes, that if the remarkable fact above 

 recorded by so accurate an observer as Richard, be exact, Clusia cannot belong to Gut- 

 tiferce, but must constitute the type of a distinct family nearer to the Marcgraaviacea. 



Choisy, in 1822, in a memoir upon the family of the Guttifercef, ascribes in its ordinal 

 character features altogether different from those of Jussieu, and equally opposed to the 

 description of Gaertner. He states that the seeds are without albumen, that the embryo 

 is erect, and that the cotyledons are large, fleshy, either separable or combined in one 

 mass. In Garcinia, he says, the seeds are arillate, and the cotyledons thick and con- 

 joined ; but in Clusia he declares that these presumed cotyledons are separable, a feature 

 that no succeeding botanist has verified. He alludes in no way to the very different 

 structure recorded by Richard, of the seed in Clusia, although, when he stated the 

 separability of the cotyledons in that genus, this idea may probably have been derived 

 from some indistinct recollection of the analysis of that eminent carpologist. 



The description of the Guttiferce in DeCandolle's celebrated ' Prodromus ' (1824) is 

 confessed to be a mere recapitulation of the above-mentioned memoir, and consequently 

 the same characters are there repeated upon the authority of Choisy. 



Cambessedes, in a very able essay upon this Natural Order, and on its relation to the 

 Temstrcemiacece, published in 1828 j, affirms that throughout the family of the Guttiferce 

 " l'embryon est droit, les cotyledons sont grands, epais, tres entiers, soud^s ensembles ; 

 la radicule est tres petite, en forme de mamelon ; sa direction, relativement au point 

 d'attache de la graine, merite la plus grande attention, et demontre jusqu'a 1' evidence, 

 que dans les families les plus naturelles, les caracteres, considered dans la plupart des 

 cas comme de la premiere valeur, peuvent varier dans les genres d'ailleurs extremement 

 voisins. Dans le Clusia Criuva, dont je possede des graines dans un etat parfait de 

 maturity, la radicule est tournee vers l'extremite de la graine la plus eloignee du point 

 d'attache." I shall presently demonstrate that this statement is founded on error, and 

 that the inferences above drawn are illusory. In that memoir the embryos of Clusia and 

 Calophyllwm are described as being erect, inverted, the small mammaeform point, which 

 he calls the radicle, as being at the apex or opposite extremity to the basal hilum of 

 attachment ; while in those of Mammea and Mesua, the radicle is said to be small, and 

 pointing in a contrary direction, that is to say, to the basal point of attachment. He 

 therefore erroneously concludes, that in this family the embryo is either homotropal or 

 antitropal, or in other words, that the radicle is sometimes directed to that point of the 

 seed next the hilum, at others, towards the opposite extremity. It is, however, fair to 

 mention that he had not confidence in the correctness of these observations, and stated 

 his doubts on this point, for the guidance of future botanists. 



* Ann. du Mus. xx. 463. f Mem. Soc. Phys. de Geneve, torn. i. % Mem. du Mus. xvi. 369. 



