260 Dr Dickson 07i Diplostemonous Flowers, dtc. 



Fig. 11. Arrangement in Koelreuferia, as described in the text. As in Oardio- 

 spermum, the petal alternating with sepals 3 and 5 aborts. 



Fig. 12. Young flower of Agrostemma Flos-Jovis, just before the appearance 

 of the carpels. The younger stamens are internal to the older 

 ones. 5, sepal ; p, petal ; st, older stamea; si', younger stamen. 



Fig. 13. Young flower of Cerastium triviale, at same stage as the last. The 

 younger stamens, as in Agrostemma, are internal to, or on a higher 

 level than, the older ones, sa, sp, si, anterior, posterior, and lateral 

 sepals ; p, petal ; st, older stamen ; st', younger stamen ; ax, convex 

 extremity of the floral axis ; b, b, lateral bracts, with secondary 

 floral axes fl'^, fl^, developed in their axils. 



Fig. 14. (From Payer). Young flower of Monsonia ovata. s, sepals ; p, petals ; 



et^, older and inner (primary) stamens, superposed to the sepals ; 

 et°, younger and outer (accessory) stamens, superposed in pairs to 

 the petals ; cp, carpels, superposed, as in Geranium, to the petals. 



Fig. 15. (From Payer). Andrcecium and pistil from a flower of 3Ionsonia ovata, 

 at the time of blossoming. Each of the primary stamens has 

 become connate with the two accessory stamens adjacent to it, one 

 on either side, so that the andrcecium seems now composed of five 

 phalanges superposed to the sepals. 



The Classification of Animals based on the Principle of 

 Cephalimtion. No. I. By James D. Dana. Communi- 

 cated by the Author.* 



(Continued from page 102). 



3. Classijication of Animals. 



1 . Subkingdoms. — Of the four subkingdoms, first recognised by 

 Cuvier and since by most zoologists, the Vertebrate, Articulate, 

 and Molluscan, are typical, or of the true animal-type, and the 

 Radiate is degradational, being plant-like in type. Using the 

 terras alphatypic, betatypic, and gammatypic, simply as a numbe7'- 

 ing of the grades of types (see p. 96), their relations are as fol- 

 lows : — 



Alphatypic, . . . .1. Vertebrates. 

 Betatypic, . . . .2. Articulates. 



Gammatypic, . . . .3. Mollusks. 

 Degradational, . . . .4. Radiates. 



An important dynamical distinction between Mollusks and 

 Articulates has been already suggested by me. 



2. Classes of Vertebrates, Articulates, Mollusks, and Radiates. 

 — (1.) The classes of Vertebrates are four (see page 78), 



* From the American Journal of Science and Arts, Vol. xxxvi., Nov. 1863. 



