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Part HI. — Seventeenth Annual Report 



(2.) The individuals of a race, both in their separate characters and 

 in the combination of all their characters, are the fortuitous examples or 

 forms of an ideal type, which is obtained from the average of all the 

 characters of every individual. It is as if nature were ever aiming to 

 arrive at this ideal and thus presented different combinations of characters 

 in every individual, and different grades of variation in every character. 



(3.) Every individual presents the same average amount of variation 

 (in the combination of all the characters) from the ideal type, but each 

 individual presents a different permutation of the separate variations of 

 the series. 



(4.) The ideal type of a race and the extent of the degrees of 

 variation in the different characters appear as the expression of the 

 living-conditions regarded as a //-hole, with all their internal combina- 

 tion, organisation, and cyclically recurring changes. The individuals are 

 the expression of this organisation and changings of the living-conditions. 



(5.) The existence of local races is certain, and they differ from one 

 another in the same characteristics as species from allied species. 

 As a rule these differences are smaller, but not always. Thus comparing 

 the pilchard, sprat, and herring with regard to the average number of 

 vertebrae, the sprat has 48, the pilchard 52, and the herring 56. But 

 in the Norwegian spring-herring the average is 57*6, and in the herring 

 from the White Sea the average is 53*6, so that the difference with 

 regard to this character between two races of one species is as much as 

 that between the two species of pilchard and herring. 



(6.) Those more separated by geographical or rather physical condi- 

 tions differ more also. So far as geographical conditions are concerned 

 they may or may not be nearly allied, and complex conditions in the 

 surroundings may even call forth in (geographically) the same region 

 distinct season- races, as spring- and autumn-herring. As will be shown, 

 the differences between these must be deeply grounded in nature. 



(7.) The result of the study — that small groups of races differ from 

 one another in certain characters in striking fashion will help us in the 

 future, on the way to the physiological solution of race-differences, when 

 we know better the physiological signification of the organs and the 

 nature of the life-conditions. 



(8.) The race-characteristics, so far as present evidence goes and until 

 proof of the opposite is forthcoming, are to be considered as hereditary. 

 Thus the herring of Schley, examined in May 1878, and again in April 

 1888, presented the same averages for the characters — the differences 

 lying within the limits of the possibility of the variation of the average.* 

 It follows, then, that the young of the Schley spring-herring when they 

 have grown to maturity return to the place of their birth in order to 

 spawn. And so we may conclude for others. The place of their birth, 

 of course, must not be construed as this or that particular square mile of 

 the sea, but as being a place where the conditions of ground and water 

 are always the same or similar. 



(9.) The dwelling-areas of the herring, wmich they do not leave as a 

 rule, are large, but vary in extent. This is a most important practical 

 conclusion, but in order to see its full significance we must first discern 

 the races into which the herring as species is divided, and then consider 

 the question of migration. 



The herring as species is naturally divided into two great groups of 

 races — the sea-herring or autumn-spawners, and the coast-herring or 



*VoLII., pp. 31 to 42, Tables IX.-XXI. 



