GENERAL CONCLUSIONS. 807 



tion applicable! Of the 120 kinds of coral enumerated by 

 Ehrenberg in the Red Sea, l 100, at least, exist under the same 

 conditions. The majority of species, originating in uncalled-for, 

 unstimulated, unselected departures from parental structure, 

 establish themselves and flourish independently of external in- 

 fluences. All classes of animals exemplify this independence : 

 the Cetaceans, under an extraordinary and nicely graduated range 

 of generic and specific modifications ; and the same may be said 

 of most Fishes. 2 



So, being unable to accept the volitional hypothesis, or that 

 of impulse from within, or the selective force exerted by out- 

 ward circumstances, I deem an innate tendency to deviate from 

 parental type, operating through periods of adequate duration, to 

 be the most probable nature, or way of operation, of the second- 

 ary law, whereby species have been derived one from the other. 



It operates, and has operated, in the surface-zones where the 

 chambered cephalopods floated, and at the depths where the bra- 

 chiopods were anchored, as in the more defined theatre in which 

 the various polypes of the coral reef display their diversities of 

 colour, size, shape, and structure, independently of outward in- 

 fluences. This tendency, moreover, is not exemplified in the 

 ratio of the number, variety, or force of conceivable ( selective ' 

 surrounding influences, but is directly as the simplicity of the 

 organism. In the Foraminifera, e. g., it is manifested in such 

 degree that as many as fifteen genera defined by one given to — 



Intrigue with the specious chaos, and dispart 

 Its most ambiguous atoms with sure art ; 

 Define their pettish limits, and estrange 

 Their points of contact and swift counterchange, 



have been found by his followers to be but varieties of a single 

 type ; and even this, too inconstant to come under the definition 

 of a species given in p. 792. The departure from parental form, 

 producing the beautiful varieties of perforate and imperforate 

 Rhizopods, and which exemplify each group, respectively, under 

 the Lagenine, Nummulinine, Globigerine,or under the Gromiine, 

 Milioline, and Lituoline types, has effected its ends independently 

 of inner volitions or of outer selections. Certain encrusting forms 

 seem by the presence of siliceous spicula to have been derived 

 from sponges ; but no explanation presents itself for such transi- 

 tional changes, save the fact of anomalous, monstrous births — as 

 these varieties, and the whole assemblage of alternate-generative 

 phenomena, would be called ' in high life.' 



1 cccxix". p. 46. 2 xcix'. p. 44. 



