STRUCTURE.] ACOTYLEDOXS NAKED SEEDS. 69 



la gaine enveloppera de meme Teusemble des feuilles suivantes 

 avant leur developpement." (Annales des Sciences, 2nd ser. 

 xi. 350.) 



It is gratifying to find a morphological speculation 

 confirmed upon such authority. I say confirmed, because, in 

 fact, M. de Jussieu admits all that is essential in the theory 

 as originally propounded. I certainly did not mean that the 

 whole cotyledon of a monocotyledonous embryo was neces- 

 sarily rolled from end to end around the plumule, but that 

 the whole or a part was in that condition. 



The ACOTYLEDONOUS embryo is not exactly, as its name 

 seems to indicate, an embryo without cotyledons ; for, in that 

 case, Cuscuta would be acotyledonous. On the contrary, it 

 is an embryo which does not germinate from two fixed 

 invariable points, namely the plumule and the radicle, but 

 indifferently from any point of the surface; as in some 

 Arads, and in all flowerless plants. See Mohl, Bemerkungen 

 itbcr die Entwicklung und den Ban der Sppren der Crypto- 

 gamischen Gewdchse : Regensb. 1833. 



16. Of Naked Seeds. 



By naked seeds has been understood, by the school of 

 Linna3us, small seed-like fruit, like that of Labiates, Borage- 

 worts, Grasses, and Sedges. But as these are distinctly 

 covered by pericarps, as has been already shown, the expres- 

 sion in the sense of Linnaeus is incorrect, and is now aban- 

 doned. Hence it has been inferred that there is no such thing 

 in existence as a naked seed ; that is to say, a seed which 

 bears on its own integuments the organ of impregnation. 



To this proposition botanists had assented till the year 

 1825, when Brown demonstrated the existence of seeds 

 strictly naked : that is to say, from their youngest state desti- 

 tute of pericarp, and receiving impregnation through their 

 integuments without the intervention of style or stigma, or 

 any stigmatic apparatus. That learned botanist has demon- 

 strated that seeds of this description are uniform in Conifers 

 and Cycads, in which no pericarpial covering exists. But we 



