AND PECULIAR FORM OF THE EMBRYO IN THE CLUSIACE^E. 247 



neck of the inner integument, as well as with the somewhat lateral aperture in the outer 

 shell, and the termination of the cord already described ; on making a longitudinal section 

 of the nucleus, this cleft is more distinctly seen, and at the bottom of this commissure is 

 observed a small prominent point, and also in the axis extending from this spot to the 

 small tubercular point at the base is seen a continuous line, more or less narrow, some- 

 what curved, and of a more opake and whiter colour than the body of the nucleus : the 

 principal mass is of a semi-crystalline hue. 



This internal thickened line is what Gaertner considered to be the embryo of the seed, 

 and the fleshy surrounding mass to be copious albumen. Choisy, Cambessedes, and most 

 other botanists, have considered the main body of the nucleus to be two large cotyledons 

 agglutinated into one solid mass, the line of their junction being indicated by the curved 

 bine just mentioned, while they held the nipple-shaped protuberance to be the radicle. 

 In the description above given, I have been careful to avoid the use of technical names in 

 designating the several parts, until the whole evidence has been stated ; but the inferences 

 I have drawn from these facts, which I will here endeavour to substantiate, are, that the 

 seed is enveloped by an entire arillus, with a raphe extending from the hilum, or basal 

 point of its attachment to the arillus and placenta, to the process or cup-shaped ring 

 surrounding the aperture situated near the geometrical apex of the testa, and through 

 which the nourishing vessels of the raphe pass, to unite with the inner integument : the 

 small cicatrix at the opposite extremity of the testa, near the hilum, must be considered 

 as the micropyle. Most botanists will perhaps call this extremity the base of the seed, and 

 correctly so, although others have considered the geometrical apex as the true base, because 

 it was once the base of the ovule before it became reversed in its position by its anatropal 

 development : the use of this term, unless accompanied by an explanation of the sense in 

 which it is applied, leads constantly to error and confusion*. The existence of the internal 

 chalaza in the contracted and thickened summit of the inner integument, and its connexion 



* Great mystification is often created by the misapplication of the several terms umbilicus, hilum, apex or base of 

 the seed, which are used in a contrary sense by different botanists ; and even Richard, who may be regarded as a leading 

 authority on this point, is not free from similar confusion. St. Hilaire, in his Monograph on the Brazilian Violaceee 

 (Mem. du Mus. xi. 446), accurately describes the structure of the seed in Viola to be carunculate at the point of its pla- 

 centary attachment, which he calls the "umbilicus," and the corresponding point of the testa, the "hilum," to which 

 the inferior radicle is directed, while the areolar "chalaza" is seen at the opposite extremity, or "apex." Prof. 

 Kunth, on the contrary (Nov. Gen. et Spec. v. 368), describes the seed in Viola as being carunculate at the apex by 

 which it is attached to the placenta, with a basal chalaza at the opposite extremity : the embryo is said to be inverted, 

 with its superior radicle directed to the hilum. Here we observe that two of the highest authorities apply the same 

 terms in a directly opposite sense ; the one truly, as regards the point of the placentary attachment of the seed, con- 

 sidering that point as its base, whatever be its position in respect to the axis of the fruit : the other uses the same 

 terms relatively to the direction which the seed may bear in regard to its position with the axis of the pericarp, which 

 in the instance of Viola, being suspended from the placenta, gives a reversed attitude to all its several parts : if this 

 loose glossology were admitted, how could we define the base and apex of the seeds, where they sometimes happen to 

 be erect, horizontal, and pendent in the same cell ? 



Cambessedes has fallen into an error of a similar nature in reversing the position of the seed in his representation 

 of Clusia Criuva (Flor. Bras. pi. 65. figs. 8, 9 & 10), where the stipitate support is miscalled and delineated as an 

 apical arillus, and his radicle (the true cotyledons) are seen at the base, instead of the apex of the seed. 



