ENTOMOLOGICAL SOCIETY OF ONTARLO. ' 45 



punished 1" and such is the natural result of an effort to attain to certainty, by means of 

 an uncertain method ; and no amount of investigation upoa the Sime lines, by ever so 

 competent an authority, can ever be unmistakably certain. The only conclusive verdict 

 must be obtained by an appeal to nature ; unite the differing forms, and if they have 

 " the power to produce beings like themselves who are also productive," then the species 

 is one, and the different forms are portions of it This is the law of nature controlling 

 all bisexual life, and it is extremely doubtful if there has ever been a well authenticated 

 instance of its violation. Cases have been reported of so-called diff'erent species having 

 been united, and the product carried forward for several generations, buL that simply 

 proves that the term species had been wrongly applied ; and this wrong application of the 

 term by namers and dencribers of species is traceable to the method of making species 

 exclusively from perceptible diff'erences. To illustrate the danger to which such are ex- 

 posnd in following that method, I quote the following passage from Wallace's Island Life^ 

 pp. 55 and 56. " An American naturalist, Mr. J. A Allen, has made elaborate observa"- 

 tions and measurements of the birds of the United States, and he fiads a woader.'ul and 

 altogether unsuspected amount of variatio a between individuals of the sa-ne species. They 

 diff'er in the general tint, and in the markings and distributioa of the colours ; in size and 

 proportions; in the length of the wiu'^s, tail, bill and feet; in tha length of particular 

 feathers, altering the shape of the wing or tail ; in the leagth of the tarsi and of the 

 separate toes ; and in the length, width, thickness and curvature of the bill. These 

 variations are very considerable, often reaching to one-sixth or one-seventh of the average 

 dimensions and sometimes more." 



We see in this extract, the perplexity that must nacessirily arise in the mind of 

 those engaged in studying such variable forms from their point of view, as to how far 

 this sort of thing may go before it becomes a different species. Now, man has demonstra- 

 ted most conclusively in connection with his domestic animals, that no amount of that 

 kind of variation interferes in the slightest with the various forms uniting, " and produc- 

 ing beings like themselves, who are also productive " And the same laws are operating 

 upon life in nature in the same way. Species, is a question of lineage ; not of size, form 

 or colours. These are incidental. 



Having given the manner in which I use the term species, I continue the subject of 

 variation. 



We have seen that there are a combination of influences at work in every habitable 

 portion of the globe, producing a change in the appearance of the life of each, in propor- 

 tion to the susceptibility of the species to receive the impression. That such spheres of 

 influence have a centre and a circumference, well defined although to us unperceived, 

 except by the eff"ect produced. Long residence in a locality for many generations givin" 

 the influence of that locality an opportunity to exert its utmost on the species living 

 under it, whilst propagations with the local stock will tend to produce a more distinctive 

 form of a species, acting as in-and-in breeding does in domestication. A fact well 

 illustrated by the life of Islmds, which is as a rule more uniform in appearance than that 

 of continents with their extended areas. 



Now it is an acknowledged fact that insects are notorious for spreading ; either from 

 their innate desire to migrate, or by external assistance. So the particular forms of one 

 locality are constantly getting mixed with the different forms of the same species in 

 another locality ; uniting with them, " and producing beings like themselves who are also 

 productive." It is a well-known experience of breeders in domestication, that when 

 differing strains of the same species are united, a great uncertainty exists as to what the 

 appearance of the offspring will be ; and the greater the difference is, the uncertainty 

 becomes proportionately greater. But more, we have to take into consideration not only 

 the late ancestors which we may have seen, but remote ancestry which we could not see, 

 that may have had in them strains that we never suspected, until they showed them- 

 selves in those we see. 



Now this commingling of different forms of the same species is constantly going on all 

 over the habitable globe, and given time and cpportunity a species, or its descendants, 

 could encircle the earth and produce confusion amongst the typical forms of every lcc«]itj. 



