133 Mr. J. Miers on the Styracese, 



large hilum, is seen a small scar, which closes a foramen beneath 

 it open to the interior ; and in this cavity the prominent nipple, 

 containing the extremity of the radicle, enters. In Styrax offi- 

 cinale, where the albumen is in the form of a depressed globe, 

 the embryo lies nearly in a horizontal position, with the coty- 

 ledons slightly inclined to the hilum ; in Cijrta, where the albu- 

 men is oval, the embryo lies in a more diagonal position ; but 

 in Strigilia, where the albumen is oblong, the embryo is vertical : 

 in all three cases, the radicle points to the cicatrix seen a little 

 on one side of the hilum. The structure of the fruit and seed 

 in Halesia differs from the foregoing in many essential respects, 

 as I will presently show ; but in every case throughout the Sty- 

 racece it is totally unlike that existing in the SymplocacecB. 



It is important to notice here, that the external shell of the 

 seed above-mentioned is in no way analogous to the outer osseous 

 tunics which I have described in the families of the CanellacecBf 

 Wintei^acecSj and Lardizabalacecs, and which I have shown to be 

 arillous in their nature. Nor can it be compared to the bony 

 shell of the Clusiacece and MagnoliacecSf where it constitutes a 

 tunic lying within the fleshy coat that bears the raphe. Here 

 the position and course of the raphe prove that in the Styracinece 

 the osseous shell of the seed is the proper testa, originating from 

 the growth of the primine of the ovule : we see that the whole of 

 its fleshy mesodermic tissue has become solidified* by the depo- 



* This oiFers a strong confirmation of the view I have taken of the 

 nature of the bony shell in the seed of Magnolia, which by a few eminent 

 botanists has been thought to result from a deposition of sclerogen upon the 

 inner face of the primine, leaving the outer face transformed into a thick 

 fleshy aril-like coating containing the vessels of the raphe ; and as these 

 two integuments are considered to be one, it has been termed " a baccate 

 testa." On the other hand, I have suggested reasons why these coats 

 should be regarded as essentially distinct, both in their nature and origin. 

 I refer the reader to those arguments {huj. op. 3 ser. i. 280), which show 

 the improbabihty that one half of the tissues of the primine should become 

 converted into a thick bony shell, while the other half remains soft 

 and fleshy. On the contrary side, this last-mentioned view is defended by 

 citing the case of the fruit of the Almond {huj. op. 3 ser. i. 357), where 

 the nut is supposed to be formed by the deposition of sclerogen upon the 

 endoderm of the young carpel, leaving its outer surface unchanged in its 

 nature to become the fleshy part of the fruit. But this conclusion appears 

 to be founded on an unsound basis, because we have convincing evidence, 

 from the position and course of the fila nutritoria (from their origin in the 

 torus to the funicle of the seed), and also from the presence of tlie woody 

 fibres in the substance of the nut, resulting from the lignification of the 

 nerves of the carpellary leaf, that the nut of the Almond is a solidification 

 of the entire carpel, and that its fleshy covering is the growth of an expan- 

 sion of the torus, as DeCandolle has shown (Organ. Veg. ii. 40. tab. 43. 

 f. 1, 2), citing Nuphar as an example, where a thick fleshy covering, ana- 

 logous to the coating over the Almond nut, surrounds the united carpels, 

 without any portion of its substance being interposed between them, which 



