118 PHYSIOGNOMY OF PLANTS. 



acquainted by gardens, descriptions,, or herbariums), than there 

 are known insects. According to the average of the state- 

 ments which I have received from several of our most distin- 

 guished entomologists whom I have had the opportunity of 

 consulting, the number of insects at present described, or 

 contained in collections without being described, may be 

 taken at between 150000 and 170000 species. The rich 

 Berlin collection does not contain less than 90000 species, 

 among which are about 3000 Coleoptera. A very large 

 number of plants have been collected in distant parts of 

 the globe, without the insects which live on them or near 

 them being brought at the same time. If, however, we 

 limit the estimates of numbers to a single part of the world, 

 and that the one which has been the best explored in re- 

 spect to both plants and insects, viz. Europe, we find a very 

 different proportion; for while we can hardly enumerate 

 between seven and eight thousand European phsenogamous 

 plants, more than three times that number of European 

 insects are already known. According to the interesting 

 communications of my friend Dohrn at Stettin, 8700 insects 

 have already been collected from the rich Pauna of that 

 vicinity, (and many micro-Lepidopterse are still wanting), 

 while the phsenogamous plants of the same district scarcely 

 exceed 1000. The Insect Fauna of Great Britain is esti- 

 mated at 11600 species. Such a preponderance of animal 

 forms need the less surprise us, since large classes of insects 

 subsist solely on animal substances, and others on agamous 

 vegetation (funguses, and even those which are subterra- 



