240 Miscellaneous. 



present anything resembling zoological regions, or centres of creation 

 characterized by one or more special types — regions and centres the 

 existence of which has been demonstrated for most of the other classes 

 of the animal kingdom. 



5. The tendency to the diffusion of the genera and subgenera is 

 counterbalanced by the tendency to restriction, which is no less 

 distinct, in the species. 



6. The number of species common to two continents, to two 

 hemispheres, to the eastern and western seas bounding a continent, 

 &c., if not absolutely nil, is always exceedingly restricted. The 

 species of the same genus sometimes change at very small distances. 

 The author has not found a single species to be common to the 

 French Atlantic coasts and to the shores of the Mediterranean. 



7. Marine currents may explain the rare exceptions to the law of 

 the local restriction of species. Thus M. de Quatrefages found at 

 Saint Jean-de-Luz the large West Indian Eunice Rousseaui, con- 

 founded by Cuvier with the E. gigantea of the Indian Ocean. This 

 species had evidently been conveyed from the West-Indian seas by 

 the Gulf-stream. 



8. From the cosmopolitism of the types and the local restriction of 

 the species, it is evident that the corresponding geographical terms 

 must be sought only among the latter. These are indeed almost 

 always found, even in the case of those species which are most 

 remarkable for some peculiarity of organization &c. 



9. The class of Annelida, as regards the perfection of the organism, 

 does not present the differences in correspondence with the latitude 

 which have been indicated in other groups, and especially in the 

 Crustacea, by Milne-Edwards. Equality of organization is one of 

 the most general laws of this group. 



10. The nature of the coast has the most marked influence upon 

 the development of the Annelidan fauna. Judging from known 

 facts, granitic and schistose coasts are in general remarkably rich in 

 species and individuals, whilst calcareous coasts are as remarkably 

 poor in both respects. — Comptes Bendus, July 25, 1864, p. 170. 



On a new Species q/Turacus. By G. R. Gray. 



A new species of the interesting genus Turacus has just been 

 brought by the Rev. C. Livingstone from the Manganja Highlands 

 of East Africa, where it was obtained at an elevation of 3000 or 

 4000 feet above the sea. 



It approaches the Turacus albocristatus in its general appearance, 

 but the crest differs in form, being as it were bicrested; viz. the plumes 

 from the crown are long and narrow, thus forming a crest pointed 

 posteriorly, while those on the occiput are very short and closely set 

 upon it. All the plumes of both parts are tipped with white. The 

 rest of the plumage is very similar to that of T. albocristatus ; but 

 the feathers of the back and wings are margined with shining golden 

 green instead of bluish green, as is seen on the latter-mentioned species. 



I propose the name of Turacus Livingstonii, as a slight acknow- 

 ledgment of that gentleman's merit in adding so interesting a species 

 to our knowledge of this showy genus.— Proc. Zool.Soc. Feb. 9, 1864. 



