196 Mr. B. Clarke on Relative Position ; 



mately connected, and hence it may be regarded as the more 

 highly developed ; and the three subdivisions, Phytolaccal, Peti- 

 verial, and Proteal, being alone Proterocarpous in their apetalous 

 foi'm (excluding the Urtical), may especially on that account be 

 so regarded ; and of these again the Proteal is the first, in the 

 flowers being irregular and the carpel more constantly anterior. 

 This subdivision, it will be seen, contains in its polypetalous form 

 Leguminosse, which Endlicher on other grounds came to the 

 conclusion were the most complicated or highest developed form 

 of Exogens. 



It differs from the Heterocarpous Division also in the frequent 

 occurrence of irregularity of the corolla, which is comparatively 

 rare in that division and confined to sections of the Orders. It 

 is also vei'y rarely apocarpous, less frequently polycarpous (and 

 then seldom with more than one whorl of carpels), and more fre- 

 quently exalbuminous. 



And lastly, there is some difference in the medical properties, 

 the Proterocarpous Division being remarkable for the absence of 

 febrifuge alkaloids, the bitter tonics also being less stimulant ; 

 while, on the other hand, narcotics strictly so called are almost 

 exclusively to be found here. 



The Subdivisions. 



The principal object in arranging the Alliances in Subdi- 

 visions is to endeavour to show the mutual relation borne to 

 each other by the monopetalous, polypetalous, and apetalous 

 divisions of Exogens, an aflinity so close, that most of the subdi- 

 visions form natural assemblages*. In the formation of these 

 and of the Alliances, I am much indebted to Dr. Lindley's valu- 

 able work the ' Vegetable Kingdom.' 



Rhizanths. 



From the affinities of Rhizanths it might be expected that the 

 position of the carpels would correspond with that of the Aral 



* The following remarks of Schleiden on the development of the corolla 

 and other parts of the flower also show the monopetalous corolla to be a 

 character of minor value : — " All foliar organs of the flower, though they 

 may subsequeutly unite in growth, first arise entirely free parts ; and if they 

 belong to one circle, they are at their earliest rudiments, and for some 

 longer or shorter time after, exactly like each other ; so that the coherence 

 of these several members and their symmetrical development is a later pro- 

 cess. I have been able readily to trace the most irregular flowers up to the 

 condition of bud in reference to this ; as, for instance, the flowers of the 

 Leguminosae, of the Labiatae, the Scrophulariacese, and the species of Aco- 

 nitum, and these fully established the laws laid down here." (Dr. Lan- 

 kester's Translation of Schleiden's Principles of Scientific Botany, p. 330.) 



