y* 



#' 



3 



xxx\ 



NUMBER OF LIVING SPECIES. 



271 



wliicli tliey are separated one from tlie other, observed that 

 by some botanists the number of known species of flowerin^r 

 plants is assumed to be under 80,000, and by others over 

 150,000.^ 



imao-ined 



^ „_ ^^ j-j. T v^ ^J^^V/XOO \JJL 



insects in tlie world for each plia3nog-amous plant : but if we 

 maj judge from tlie relative proportion of tlie two classes in 



must somewhat 



that estimate ; for the total number of British insects ^ ac- 



cor 



g to a census maae m laaa, was about 12,500.t 



mammifers 



exceeded 800, and according to Mr. Waterhouse more than 

 1,200 were ascertained to exist in 18504 Baron Cuvier esti- 



wn 



Mr. 



numb 



Museum 



that about 9,000 were known to the ichthyologist even before 





America 



to have discovered at least 1,000 new species. We have still 



sive of insects. 



invertebrated 



mere matter 



what proportion the aquatic tribes may bear to the denizens 

 of the land ; but the habitable surface beneath the waters 

 can hardly be estimated at less than double that of the con- 



admit 



life 



area is destitute of life, in consequence of great depth, cold 

 ^^-^-less, and other circumstances. The ocean teems with 



the class of Polyps alone {G eel enter at a) are conjectured 

 by Lamarck to be as strong in individuals as insects. Every 

 tropical reef is described as covered with corals and spon-es 

 and swarming with crustaceans, sea-urchins, and moUusks ,' 

 while almost every tide-washed rock in the world is car- 



some 



- 7 ---^^ ^ujj|juiLs some sea-anemones [AcUmce), 



^orailmes {Bryozoa), and Testacea. There are also para- 



number 



1859^^'''' ^^ Tasmania, vol. i. p. iii. 



t See Catalogue of Brit. Insects, by 

 John Curtis, Esq. '^ 



xnree or tour ot which are 



I Mr. G-. Gray, in his genera of 

 birds (1834) enumerated 8,000 species; 

 Prince Charles Bonaparte, in 1854, 

 8,300. 



