( Ixxviii ) 



the higher and lower forms of life. I am indebted to my 

 friends the authors for the followmg figures ; — 



In COLEOPTERA I 



the species already dealt with in the Biologia are 10,916 



not yet dealt with 4498 



the approximate total number ahvays subject \ 



to be increased by additional discoveries : I 



including about 8,800 7iew species and 360 [ 



new genera, are thus j 



2328 

 4372 



1183 



2817 



In Lepidoptera 



the species already dealt with are 



not yet dealt with 



Total number subject to further increase : \ 

 including about 3250 new species J 



In Hymenoptera 



the species already dealt with are 



remaining to be dealt with 



subject to very considerable increase, as] 

 the Hymenoptera are generally supposed to • 

 equal the Coleoptera in numbers j 



In Dipteea 



total number of species to hand are at least 

 of which about one-half are new. These are 

 also a mere fraction of the total number of 

 species existing which may possibly be equal 

 to the Coleoptera or to the Hymenoptera. 



In Hemiptera 

 a fraction only of the Heteroptera amount- 

 ing to about 



and of the Homoptera about 



1600 of which are probably new, bring the 

 list of known, if not all described, species of 

 insects in that very limited portion of the 



globe to no less than 



leaving the Orthoptera and Neuroptera at 

 present untouched ; the proportion of new 

 species throughout being at least 43 per cent, 



Comparing these figures with the numbers of mammals, 

 birds, &c., from the same area we get — 



Mammalia 



Aves 



Eeptilia 



In this total a proportion of less than 5 per cent, are new. 



2000 

 1000 



15,414 



6700 



4000 



1000 



3000 



30,114 



180 



1600 



157 



1937 



An estimate of about 1000 species of Arachnida would 

 raise the proportion of novelties considerably, this branch of 



