450 Zoological Society : — 



character, and one of the most important. If the degree of 

 civihzation of the country allows us to ascertain exacth' the 

 proportion of these great kinds of station, it will be well to give 

 it in a numerical form. In this case the numbers express what 

 is essential to be known, in an exact and condensed form. 



After this, I regard it as important to ascertain the commonest 

 species in the stations which occupy the greatest amount of space, 

 and in particular the social arborescent species, that is to say, 

 those of w^hich the forests are exclusively composed. In highly 

 cultivated countries the indication of the principal agricultural 

 species is almost of equal importance. 



In the third degree of importance I should place the enume- 

 ration of the principal genera, the indication of the predominant 

 and characteristic families, the frequency or rarity of certain 

 great physiognomical categories, such as succulent plants, ever- 

 greens, annual plants, &c. 



Lastly, I should give the lowest place to the characters which 

 only a botanist can discover, or which result solely from a com- 

 plete investigation, and from calculations made from books, — 

 such as the indication of rare species, the proportion of the 

 Dicotyledones to the Monocotyledones, the total number of species, 

 genera and families, that of the species peculiar to the country, 

 and the average number of species to the genera and families. 



The analogies and discrepancies, in relation to other countries, 

 have more or less value according as they repose upon one or 

 other of the characters, of very different degrees of importance, 

 to which I have just referred. These reflections appear to me 

 to be adapted to the guidance of the authors of Floras, and 

 travellers who describe vegetation. They show to the former 

 that there ai'e some numbers which it is useful to calculate, and 

 others that are useless or even deceptive ; and to the latter that 

 certain essential facts are not evident on the spot or to the eyes. 



PROCEEDINGS OF LEARNED SOCIETIES. 



ZOOLOGICAL SOCIETY. 



January 24, 1854. — Dr. Gray, Vice-President, in the Chair. 

 A Monograph of the Genus Ruticilla. By F. Moore. 



Genus Ruticilla (Ray), Brehm. 

 Syn. Ficedida, Boie. Phoenicura, Swains. Chaimarrornis, Hodgs.* 



1. Ruticilla ph(enicura, Linn. 



Syn. Motacilla phoenicuriis, Linn. S. N. i. p. 335. 



Sylvia phoenicurus. Lath. Ind. Orn. ii. p. 511; Gen, Hist. \i\. p. 21. 



Ruticilla sylvestris, Brehm, Voeg. Deutschl. p. 363. t. 21. f. 4. 



* Altered to Chaemarrhoniis by Agassiz, in his ' Nomenclator Zoologicus'. 



