■U NATURAL HISTORY OF PLANTS. 



The family thus understood " by concatenation " has many 

 affinities. By the isostemonous Euonymeœ with ascending ovules, 

 it approaches the Penœaceœ, from which we shall find it differs 

 chiefly in the organisation of its gyntecium ; and the Bhamnacece, 

 from which we shall distinguish it by one absolute character — the 

 isostemony of the latter, with oppositipetalous stamens. By the 

 Buxecc, and also by the Hippocrateœ and Uuom/meœ, it presents 

 great resemblances to certain Euphorbiacece. But in the latter, 

 which never have more than one or two descending ovules in each 

 cell, the micropyle is directed upwards and outwards, whilst, in the 

 corresponding cases, it is interior and superior in the Cclastraceœ. 

 The latter also approach the Staphyleœ (which are Sapindaceœ) and 

 the Hicineœ ; but these last have been rightly referred to the families 

 with gamopetalous corolla ; and the former, closely allied as they are 

 to the Cclastraceœ, especially the ïlippocrateœ, are distinguished 

 from them either by the independence of their carpels, by their 

 composite leaves, by the organisation of their fruit, by the form 

 of their floral receptacle, and consequent mode of staminal insertion, 

 by the isostemony of their andrœcium, or especially by several 

 of these characters combined. The impossibility of establishing, by 

 one or more technical characters, an absolute difference between the 

 Celas traceœ and the various groups with which we have just compared 

 them, arises from the fact that they themselves have not a single 

 character which is not sometimes wanting. "When their ovules are 

 definite in number, they are ascending with the micropyle primarily 

 exterior, or descending with the micropyle interior, but they may be 

 neither descending, nor ascending, nor definite in number. Their 

 floral receptacle is often convex or plane, and the insertion is then hy- 

 pogynous ; but the receptacle may, here and there, become extremely 

 concave ; ] which entails the' perigyny of the perianth and andicc- 

 cium. Their aerial branches are ordinarily woody ; 2 but this character 

 may sometimes be wanting in the exceptional type of Staclchousia. 



1 As in Mortonia, and, to a less degree, Per- mid ScKting. PJt. Tubing. (1827), § 75. On that 



rottetia, including C'ari/ospermum, of which it has of Euonynms: Lindl. Introd. i. 213. Oliver 



been rightly said that they are BhamnacecB, {Stem Dicot. 25) says that the organisation of 



except that their stamens are altcrnipetalous. the woods of Salvadora deserves the attention 



- The structure of the Cclastraceœ is espe- of botanists. We have pointed out in our 



cially interesting in the climbing species, as Monogr. des Buxaceœ, the structure of the 



Celastrus, where we have seen the woody axis branches of Sarcococea (7), of tho stems of the 



divided into three lobes, the separation being Boxes (8), of the rhizomes Pachysandra (10), of 



indicated externally by furrows spirally crossed the roots, leaves, etc. (t. 2, fig. 1-12). On the 



(A. Juss. Ma/piff/i. 117). On the stem of C. Box, see also Schacht, Ber Bourn, 195. 

 scandais, see H. Mohl, Ueb. d. Ban der Banken- 



