298 DR. H. GADOW OX EVOLUTIOX [Mar. 20, 



Animals and plants have, since the beginning of life, acquired and 

 inherited and retained whatever was better, and they have got 

 rid of imperfections, so that this whole process itself has become 

 an acquii'ed and inherited character. Thus alone can it be 

 explained that an organism can and will, under new circumstances, 

 or under new and sudden stress, react in a manner surpi-isingly 

 quick and straight to the point. 



The Gnemido2Jhori are so plastic that they still respond to 

 eveiy new condition, and in so vai'ied a country as Mexico they 

 are liable to meet with new conditions whenever they spread (not 

 migi'ate!) into regions new to them. These need not be localities 

 wdiere no Cnemidophorus has been before. The whole process is 

 now very complex. For instance, a clan of typical C communis 

 occidentalis may spread into locality A, Avhich is already inhabited 

 by C. immutabilis. Moi-e likely than not, it will there assume 

 some of those characters which the prevailing conditions produce 

 or require, and the result will be a suj)erficial resemblance to 

 C. immutabilis. Into this same locality spreads a clan of typical 

 C. mexicamos, which also assume some of the characters which 

 the aboriginal C. immutabilis possesses ; but the result in these 

 " immigrants " will not be the same, because C.inexicanus and 

 C. comiminis ai-e not the same. 



A gTeat reseml)lance between the three kinds of lizards will 

 result in obedience to the genius loci. One of these may yield in 

 the matter of pores and arm-granules and in the pattern of colour, 

 but retaining its collar ; the other set may concede nearly every- 

 thing, but may stick obstinately to some other feature by which 

 alone it proclaims its descent. Not because that point is necessary 

 to its welfare, but because inheritance happens to be too strong, 

 at least for the present. 



The whole body, i. e. the sum total of all its characters, of 

 which we can follow only a few, is considerably influenced by new 

 environmental, bionomic conditions. All the characters, being 

 therefore in an unstable condition, or shaken up, " vary " sepa- 

 I'ately ; some, however, with an obvious amount of correlation : 

 with the result that many combinations are formed — some of them 

 good, others Imd or indifierent, and thus, seemingly by accident, 



orthogenesis, tendency towards perfection, &c., may be referred to Hajckel's 

 discussion of these and similar subjects in his 'Geiierelle Morphologie der 

 Organismen,' Chap. xix. (Berlin, 1866); reprinted as Chap. ix. pp. 311-319 in 

 ' Principien dev generellen Mor])hologie der Organismen ' (;Berlin, 1906). There, p. 312, 

 he uses the excellent term Teleosis for H. G. Bvonn's " Gesetz der progressiven 

 Entwickelung." On p. 317, Ntegeli's " Vervollkommnungs-theorie," practically 

 including Elmer's Orthogenesis, is discussed. Hneckel finds fault with Nsegeli's ex- 

 pression that "all organisms have the tendenct/ to become more complicated or perfect " 

 as leading to teleology and dualism, but Ha-ckel's substitution of a "general mecha- 

 nical law of Nature " does not mend matters. 



The main purpose of an organism is to live ! Of course that, again, is not a 

 "purpose," but it is its business, Geschaeft, that what it is busv with, " das was er 

 schafft"! ' ./ . 



