406 NATURAL HISTORY OF PLANTS. 



Mitella, and Chrysosplenium, to which he erroneously added Adoxa. 

 De Candolle 1 added in 1830 Leptarrhena, Tettima, Astilbe, Donatio. 

 Vahlia, and Lepuropetalum ; the number has since been increased to 

 eighteen by the genera Boykinia, SuUivantia, Bolandra, Oresitrqphe, 

 Leptarrhena, Eremosyne, and Tohniea. All these are usually herbs 

 with a subterraneous stock, and frequently scapiform floriferous 

 branches. The leaves are usually alternate exstipulate. The flowers 

 are regular (exceptionally irregular, as in Tohniea), usually pen- 

 tamerous. The gynaeceum has one or two (more rarely three) cells, 

 complete or incomplete. 



II. Penthore^i. — This series consisting of the single genus Pen- 

 tltorum, previously referred to Crassidacets, comes very near many of 

 those genera of Saxifragece whose carpels are free above. We 

 thought it impossible to place Penthorum 2 in any other order than 

 that of Cephalotus. It differs no doubt but slightly from the 

 Crassulads, yet it lacks their fleshy succulent leaves ; and its 

 embryo, moreover, is surrounded by an albumen of noteworthy 

 thickness. It is distinguished as a series by the receptacle, in which 

 is plunged the lower half of the verticillate carpels, by the peculiar 

 insertion of the perianth and androceum, and, finally, by the rudi- 

 mentary condition of the corolla, when present. 



III. Cephalote^e. — The genus Cep/ialottts, founded in 1806, is the 

 sole representative of this series, and was formerly held the type of 

 a distinct order, 3 allied to Renonculacece, Rosacea, Franco ace <z, A &c. 

 Later on Bentham & Hooker described it as an abnormal Saxi- 

 fragad. We must note as the distinctive characters of this little 

 series the form of its ascidia and receptacle, the free carpels, the 

 ascending ovule with its micropyle downwards and inwards, the 

 perigyny of the diplostemonous androceum, and the simple perianth, 

 which perhaps represents a corolla. 



IV. Parnassle. — The only genus of this series has been referred 

 to most diverse orders. 5 It is characterized chiefly by its shallow 



1 Prodr., iv. 1-54. Here the Saxifrages form 4 J. G. Agaedh thinks these plants may be 



one of the five tribes of Saxifragacece. considered as Triuridece with hermaphrodite 



- In Andansonia, vi., 3-6. flowers and carpels. 



5 Cephalotece R. Be., in Phil. Mag. (1832).— 6 " There is an old quarrel among systematists 



Lindt,., Veg. Kingd., 428.— Cephalotacece LimrL., as to the affinities of Pamassia. Linnaeus 



A Key to Pot. (1835), n. 5. (Fragm. Meth. Nat., in Class PI., 498) spoke 



