THYMELJEAOE^. 117 



India. The greater part of the Ooeanip Thymelm are Pimeleas, to 

 the number, of nearly a hundred. To the Cape belong exclusively 

 two genera of numerous s^Qcies, Struthiola and Lachncea. The 

 genera most widely spread in the old world are: Gnida, which 

 grows in Africa, in Asia and as far as tropical Oceania; Wik- 

 stroemia, which is Asiatic and Oceanic ; Thymelcea, extending like 

 Daphnej through Asia, Africa and Europe. In America, from 

 Tierra del Fuego, where Drapetes, muscosa grows, to Canada, where 

 Dtrca palnstris is found, there ariB a hundred degrees. In our 

 hemisphere, from Tasmania and New Zealand, where the Kellerias 

 are the analogues of Drapetes, to Sweden and Norway, where also 

 Daphne grows, there is the same distance. The latter genus has 

 representatives in Java, in China and Japan, in India, in Siberia 

 aud in all the countries of Europe. 



All these plants have pretty numerous constant characters. The 

 principal are : the simplicity of the perianth ' and its imbricate 

 prefloration; the definite number of parts of the androecium and 

 their insertion on the floral envelope ; the independence of the 

 gynsecium and its insertion inferior to that of the stamens.'^ The 

 characters which vary most and which generally serve to mark 

 the generic divisions are : the number of the parts of the flower, 

 the point of insertion of the stamens aud the dimensions of their 

 filaments which render them exserted or enclosed, the presence or 

 absence of scales in the throat of the perianth and of glands forming 

 a disk at the foot of the gynsecium, the consistence of the pericarp, 

 the mode in which the base of the perianth falls after fioration or 

 persists growing round the ripe fruit, the relative proportions of 

 the embryo and albumen which may be wanting, and the arrange- 

 ment of the inflorescence. A single character distinguishes the 

 series of the Aquilarie^ from that of the Thymele.^ ; it is the 



' The comparative study of types such as must be mentioned the simplicity of the leaves, 



Octolepis, Aquilaria and Daphne, for example, the absence of stipules, and, in the organisation 



•without speaking of the intermediaries, seems of the stems, the peculiarities traceable in the 



to prove that the part considered as the tube of liber, tenaceous, sometimes textile, with the 



the calyx here represents a receptacle, bearing remarkable fascicular structure -which renders 



perigynous stamens, the true calyx consisting the leaflets reticulate, in form of cloth, lace, 



only of the parts of the limb. Payer [Organog. thread, and which prevents the branches of the 



481) arrived at the same conclusion, Adansonia, Thgmeleee from being easily and cleanly broken, 



xi. fasc. 10. (See Link, Anat. Fl. (1843), t. viii, 6.— 



s There are olher characters nearly constant A. 3vas. EUm. Dot. 65, fig. 96. — Oliv. Stem. 



in the organs of vegetation. In this respect Dicot. 31.) 



