of the Vegetable Ovule. 23 



bedded, and which is often of a scarlet colour, is common to all 

 the Eitphurbiacea ; and this is always more or less fleshy, and 

 invariably invests the bony shell usually denominated the testa, 

 but which shell, in all cases, I have found devoid of tracheal 

 vessels. 



The development of the ovule in its early stages is subject to 

 many modifications, which, in different families of plants, are 

 often constant ; and these afford good characters, hitherto little 

 noticed. Some interesting facts on this head were recorded by 

 Mr. B. Clarke, eight years ago*, when he pointed out the im- 

 portance of knowing the position of the raphe in its earliest 

 development, — a character he employed to show the relation of 

 different families in a systematic point of view, according to his 

 own peculiar notions. 



Prof. Agardh has very lately contributed a valuable collection 

 of facts upon the same head, and with the same view, to which 

 he has attached more importance than they deserve ; still, the 

 facts demonstrated by him claim our especial notice, as they are 

 accompanied by nearly 500 figures illustrative of the modes of 

 development of the ovule in 310 different genera of plants. He 

 has shown how much the position of the raphe, in regard to the 

 axis of the ovary, varies in different families, and even in different 

 genera, of the same order ; and in his novel systematic an'ange- 

 ment of Phanerogamiaf, this difference has in many cases led 

 him to break up many natural orders into distinct groups, which 

 he separates by long intervals, while at the same time he places 

 in juxtaposition other families of little real kindredship, thus 

 suggesting a distribution quite incompatible with our generally 

 received notions of real affinity. But although this new system 

 is not likely to receive the support of botanists in general, still 

 the many observations, and the numerous facts and draw- 

 ings here contributed, will show the value of the character of 

 the development of the ovule, if applied only as an accessory 

 feature. In order, however, to elicit the true value of this cha- 

 racter, it should be followed through all the changes of subse- 

 quent growth, up to the period of the perfection of the seed, — a 

 consideration not attended to in that work. I have shown the 

 importance of this last consideration in the Styracece, especially 

 in the tribe Halesiea ; and I have yet to detail developments of 

 a similar nature in other families which I have investigated. It 



* " On the Position of the Carpels when 2, and when single ; including 

 Outlines of a new Method of Arrangement of the Orders of Exogens, and 

 Observations on the Structure of Ovaries consisting of a single carpel." 

 Proceed. Linn. Soc. ii. 105. — " On the Position of the Raphe in Anatropal 

 Ovules," ibid. p. 147- 



t Theoria Systematica Plantarum : Lundae, 1858. 



