Harris Hawthorne Wilder 465 



(3) Differences occur much more frequently on the left side. 



3. The influence of the germ-plasm and its mechanism {i. e., the direct 

 control exercised by heredity) is exerted upon the friction-skin surfaces 

 only so far as concerns the general configuration, i. e., the main lines, the 

 patterns and other similar features; the individual ridges and their 

 details {minutice) are apparently under the control of individual mechan- 

 ical laws to which they are subjected during growth. Have we then 

 arrived at the limit of the control of the predetermining mechanism 

 beyond which mechanical laivs are alone operative; and is it then possible 

 to hold that the modifications in this latter field are the results of indi^ 

 vicinal experience^ and that they are similar in the various members of 

 a given species solely because of similar environment? To these and 

 similar questions we can have no answer at present; yet it seems likely 

 that in the general subject of palm and sole markings, not only in man 

 but in other mammals as well, we have a set of easily observed and very 

 significant data which may yield important results to future investigators. 



BIBLIOGRAPHY. 



I. General Works Dealing with Compound Monsters. 



Ahlfeld, 80-82. — Missbildungen des Menschen. Leipzig. [With extensive 

 atlas, in fol.] 



Barkow, 32. — Monstra animalium Duplicia. 



Bateson, 94. — Materials for the study of variation. Macmillan, London. 



Blanc, 93. — Les anomalies chez I'homme et les mammiferes. Paris. 



Creighton, 90. — Article " Monsters " in Encyclopedia Britannica. 9th ed. 



Fisher, G. H., 66. — Diploteratology. Trans. N. Y. Med. Soc. 



FoRSTER, 61. — Die Missbildungen des Menschen, systematisch dargestellt. 

 Jena. [With atlas of 26 4° plates, containing 524 figures, of which 

 162 are originals from specimens in the Wiirzburger Museum.] 



Gould and Pyle (about go). — Anomalies and Curiosities of Medicine. 



Gruber, 59. — Missbildungen. St. Petersburg. Mem. de I'Acad. imp. des 

 Sciences. 



Guinard, 92. — Precis de Teratologie; Anomalies et monstruosites chez I'homme 

 et chez les animaux. Paris. 



GuRLT, 32. — Handbuch der pathol. Anat. der Haussaiigethiere. [With atlas.] 



Hirst and Piersol, gi-92. — Human Monstrosities. Philadelphia. 



LicETus, 1665. — De Monstris. Amsterdam. [In part fabulous; mainly of his- 

 torical value.] 



Meckel. 12-18. — Handbuch der pathol. Anat. Halle. 



ig_ — De duplicatate monstrosa commentarius. Halle and Berlin. 



Nokris, 96. — Amer. Text-book of Obstetrics. Philadelphia. 



St. Hilaiee, G., 32-37. — Histoire generale et particuliere des anomalies de 

 I'organization chez I'homme et les animaux. Paris. 



ScHULTZE, O., 97. — Grundriss der Entwickelungsgeschichte des Menschen und 

 der Saugethiere. Leipzig. 



