.'U2 Mr. Griffith on the Root-Parasites referred to RbizanthefB, 



The classes of M. Endlicher, of which Rhizanthece form the tenth (or perhaps 

 the eleventh, as Selaginece and Zamice are both numbered ix.), are equivalent to 

 the alliances of Dr. Lindley. But the classes of the last distinguished botanist, 

 of which Rhizanthece form the fourth, appear to be equivalent to the regiones 

 of M. Endlicher ; so that in vi'hatever measure these botanists may agree in 

 the adoption of Rhizanthece, it is evident that their ideas of its value as a 

 natural group have no common measure of agreement. I may be also allowed 

 to remark, that a more recent classification of Rhizanthece as Sporogens*, a 

 division of the natural subkingdom Monocotyledones, shows that Dr. Lindley 

 does not entertain that fixedness of opinion which I cannot help thinking 

 would exist regarding any division, more especially one of so high a value, ap- 

 proaching to the true order of nature. 



In making Rhizanthece a class, M. Endlicher appears to have lost sight 

 of the principles of system on which his other classes are founded, the orders 

 or families of which have generally sufiiciently close relations f. The same 

 may be said of its situation between Cycadece, and, " hngo intervallo" indeed, 

 Graminece. 



Dr. Lindley, in elevating the same group to the rank of a primary division 

 of the vegetable kingdom, has avoided this more immediate consociation of 

 dissimilar plants. For a class, as he constitutes one, must have wide differ- 

 ences in organization, just as Monocotyledones include Orchidece and Naiades ; 

 or Dicotyledones, Compositce and Ceratophyllum. And it might be assumed, 

 that the hiatus between its constituent parts would be supplied by future 

 discoveries. But he has not kept in view the incongruity of Rhizanthece (and 

 his second additional class Gymnospermce) in stamp of peculiarity and variety 

 of form, in number of species and general importance, with the other three 

 natural classes (or subkingdoms) ; and he has placed the class in question 

 after^ or in§ Monocotyledones, as though such a transition could only take 



* Lindley, Elements of Botany, pp. 227, 229, 237. 



t Compare this class Rhizanthea with the classes indicated by Mr. Robert Brown here and there, as 

 that comprising Rubiacea, Apocyne<B, Asclepiadea and certain Gentianea ; or that of Malvaceee, Stercu- 

 liacea, Chlenacece, Tiliaceis and Byttneriacece ; or that of Labiates and Verbenacex ; or Dilleniaceee and 

 Magnoliacecc. 



i Introduction to the Natural System, ed. 2. p. 389. § Elements, p. 227-230. 



