286 Goleopterological Notices, VII. 



we might go further, and, in giving to the Paliearctic fauna a like 

 number of 80,000 species, tlie tropics of both hemispheres 450,- 

 000 species, and to Australasia and temperate South America and 

 Africa 90,000, state a total for the Coleoptera of the world of 

 700,000. Going still further, if we add to this 600,000 Hymenop- 

 tera, 600,000 Diptera and 900,000 of all other orders, we have as a 

 grand total for the Insecta of 2,800,000, which almost baffles belief, 

 and 3^et this estimate does not greatly differ from several others 

 which have been suggested. 



There will, of course, always be argument and dispute as to 

 what proportion of these are really species, and what so-called 

 races or varieties, but this is a question which need not especially 

 interest us at present, in view of the perfectly arbitrary meaning 

 usually attached to these terms. Species, as meant in this connec- 

 tion, are aggregates which differ morphologically from each other 

 in several constant and evident structural characters, and we can 

 proceed by no other criterion than this in our determinations, 

 until life-histories and other purely biologic matters can be inves- 

 tigated. 



To those who believe that there must neeessaril}^ be a large 

 amount of structural difference between species in the Insecta, 

 no better object lesson could be cited than that afforded by the 

 genus Lachnosterna, where forms mutually so very similar as to 

 be formerly lumped together in almost every cabinet, were shown 

 some time since to have their complicated genitalia so arranged 

 as to even prohibit sexual union. Another equally cogent exam- 

 ple occurs in the genus Reichenbachia, where the species would 

 be mutually undistinguishable, in many cases, were it not for modi- 

 fications of the male antennae, so radically divergent as to pro- 

 claim beyond peradventure their specific distinctness. In arrang- 

 ing my collection of Brazilian Barini, I have frequentl}^ been 

 astonished at the approximation of species in external form and 

 facies, there being several instances where forms are mutually 

 almost inseparable from a dorsal point of view, yet wholly dif- 

 ferent in the sculpture of the under surface or in some other 

 remarkable special manner. 



These examples are cited in order to assist in counteracting, to 

 some extent, if possible, a somewhat general movement in favor 

 of a subdivision of biologic forms into species, races and varieties 

 on wholly arbitrary assumptions. No doubt, future knowledge 



