452 



SCIENCE 



[N. S. Vol. XXVII. No. 690 



blanee. Since, by a comparison of the 

 prints, it may be seen that the resemblance 

 is confined to the general patterns while 

 there is no especial resemblance in the in- 

 dividual ridges (Galton's "minutiae") we 

 arrive at what may be called the limit of 

 germinal control, i. e., the point where the 

 directive force felt in the development 

 ceases to act, leaving further details to 

 other forces. 



Heredity in Epidermic Markings of 

 Palms and Soles ("Friction-shin").— la a 

 set of sole prints of a family, including 

 three generations, the inheritance of a defi- 

 nite configuration over certain definite 

 areas was followed by means of distinctive 

 colors. In these prints a marked degree 

 of hereditary influence was shown, espe- 

 cially in the inheritance of a "calcar pat- 

 tern," one of the rarest features in the 

 human foot. 



The Four Inseparable Factors of Evolu- 

 tion, Theory of their Distinct and Com- 

 bined Action in the Transformation of 

 the Titanotheres, an Extinct Family of 

 Hoofed Animals in the Order Peris- 

 sodactyla: Henry Fairfield Osborn, 

 Columbia University. (Published in 

 full in Science, January 24, 1908.) 



When do Variations attain Selection 

 Value?: Bashford Dean, Columbia Uni- 

 versity. 



One of the major criticisms of Darwinian 

 natural selection showed that small fluctu- 

 ating variations were not of actual value 

 in the .struggle for survival : accordingly, 

 they would not be expected to accumulate 

 in the direction of pronounced utility. 

 And it is notably this criticism which lies 

 at the base of various neo-Darwinian ex- 

 planations. In the present contribution 

 stress is laid upon the fact that variations 

 may attain selection value without an ac- 

 cumulation of small and less useful stages. 

 The stages in such cases occur, it is true, 



i. e., as small fluctuating variations, rarely 

 appearing suddenly, but they are meaning- 

 less in terms of selection. . 



This point of view was explained by a 

 series of analogies, in which there was no 

 ground to question the non-utility of the 

 stages of cumulation. For the end result 

 itself, although as highly complex as many 

 of those which are granted selection value, 

 could have had no significance in the strug- 

 gle for survival. 



Numerous analogies of this kind were 

 cited: resemblances to human face in 

 the pupffi of Feniseca tarquineus and of 

 Sphalgis s-signata, on back of death 's head 

 moths, in Taira crab, on "ear bone" of 

 whale, in seed-capsule of Antirrhinum: re- 

 semblances of tree hoppers to birds, of 

 desiccation lines on seeds to ideographs, of 

 the supraoccipital of an Indian goat to the 

 face of Entellus, of the rabbit's sphenoid 

 to a fox 's head. 



If such remarkably complicated resem- 

 blances could be attained by non-useful 

 variations, it follows that some, if not many 

 cases whose value has been debated (pro- 

 tective coloration, mimicry) may have had 

 a similar accidental and meaningless 

 origin. 



Inheritance in Canaries: C. B. Davenport, 

 Carnegie Station for Experimental Evo- 

 lution, Cold Spring Harbor, N. T. 

 Crest is a typical Mendelian dominant 

 over plain head. Plain-headed canaries do 

 not throw crests; and among crested birds 

 of the second or later hybrid generation 

 some may be obtained that produce only 

 crested offspring. Baldness is a typical 

 recessive to full head feathering. In the 

 plumage color the yeUow form is derived 

 from the ancestral "green" canary by a 

 dropping out of black pigment. The yel- 

 low canary carries, however, a mottling 

 factor, so that in P^ the green X yellow 

 gives offspring that are yellow mottled 



