[ 8] 
III. Remarks on the Nature of the outer Jleshy covering of the Seed in the Clusiaceæ, 
Magnoliaceæ, &c., and on the Deøelopment of the Raphe in general, under its various 
circumstances. By Joux Mss, Esq., F.R.S., F.L.S., $c. 
Read March 18th, 1856. 
IN a notice read before the Linnean Society on the structure of the seed of the Clusiacee, 
I described the external fleshy envelope of the seed of the Clusiee, and offered evidence 
to prove that this coating is a product of extraneous placentary growth, subsequent to the 
development of the primine, and therefore a kind of arillus. It was of some importance to 
ascertain this point, as in the tribe Tovomiteæ of the same family, the outer coating, similar 
in substance and colour, is unquestionably an aril: this is manifest from its peculiar form ; 
it is free from the testa, but may be opened out like a flat plate; itis folded round the seed 
which it envelopes and conceals, its margins being free and overlapping one another: in 
the other tribe of the Garciniee, this covering is also entire, is soft, and assumes the 
character of an enveloping pulp. 1f, therefore, in the two latter tribes, the outer coating 
be unquestionably an aril, it was fair to conclude that the analogous envelope in the 
Clusiacee is of a similar nature. This inference was still farther confirmed by the 
presence of a distinct simple raphe, which extends from the base to the apex of the seed 
_ beneath the inner pellicle of the aril; it lies within a groove of the testa from which it is 
wholly free, the apex of which it perforates, and becomes lost in the chalaza of the inner 
integument. Under the evidence of such demonstrative proof, as far as regards the, 
Clusieæ, I was led to institute a comparison of similar facts observable in the Magnoliaceæ, 
because, if that coating be considered an aril in the one family, it must be of the ume. 
nature in the other. I then referred to the admirable work of Dr. Asa Gray (‘The 
Genera of the Plants of the United States’), where a different view is entertained : = 
the external fleshy coat of the seeds of Magnolia is described as the testa, and er 4 
bony shell as the tegmen, or inner integument, the true tegmen having estaper Å 5 
notice of that excellent botanist. In opposition to this view, I referred to tha eu 
had made many : years before, of the seed of Talauma, à er re ibed by 
Magnolia: the evidence then collected, convinced me that the ‘testa’ på - 
Dr. Gray is arilliform, and that his * tegmen ’ is the true testa. If we ng c this i z 
coating in Talauma, where it is entire, we find it easily detached from må pi Is gå 
shell; and if we begin to pull it away from the summit, the raphe, as å adis en 
à : 5 ae er rresponding groove which 
be seen quite free from it, as in the Clusieæ, and to lie in a correspo : Mn 
extends from the base to the apex: the upper end of this raphe is rn scm ied 
aperture near the summit of this osseous shell, and to become lost in ies ms 
chalaza of a membranaceous inner integument. To all appearance, the raphe 
; : 1 
quite free; but if we examine it more attentively, a corresponding portion of the extremely 
VOL. XXII. 
M 
