6 Herr Max Weber on the Origin of Hair 



The response to this question must be connected with my 

 observation already mentioned, that the hairs appear behind 

 the scales, never upon them. In consequence of this I came 

 to the conclusion that the hairs are dependent upon the scales 

 in their arrangement. If the scales are imbricated, which 

 was probably the primitive condition, the hairs must conse- 

 quently form alternating rows and groups. Now what will 

 happen when the scales disappear ? Will the hairs preserve 

 their arrangement, as though they still stood behind scales, 

 or will they lose this regular formation ? In the event of the 

 first-mentioned case, we might conversely find in it the proof 

 of the former presence of scales. The question to be 

 answered would therefore be, whether in scaleless Mammals, or 

 upon regions of the skin without scales, the hairs are so 

 arranged as though they stood behind scales. 



The abundant literature upon the subject of hair supplied 

 no answer upon this point, since beyond incidental observa- 

 tions, with which there was really nothing to be done, it 

 contains nothing that touches the question. Now this problem 

 has been made by Heer J. C. H. de Meijere * the object of an 

 exhaustive investigation, which was conducted in my labora- 

 tory, and Avill shortly also be made accessible in a German 

 form to a wider circle of interested students. De Meijere 

 examined two hundred and twenty species of Mammals, and 

 arrived at various surprising results, of which the following 

 is the only one that here concerns us. In the great majority 

 of cases the hairs are arranged in alternating groups, which 

 are formed in very different ways. As a primitive and very 

 simple condition must rank a group which consists of three 

 similar hairs "f. Usually, however, the hairs in a group are 

 more numerous. At the same time the hairs may issue from 

 isolated follicles or form bundles, De Meijere distinguishes 

 false bundles, which have arisen through fusion of follicles, 

 and genuine bundles. The latter probably arose through 

 the formation upon a follicle of several secondary ones by 

 means of budding. It is an important fact that bundles of 

 this kind also appear in alternating groups. Now if we 

 further consider that upon the scale-bearing portions of the 

 integument the hairs represent alternating groups, and that 

 upon the scaleless portions they frequently form exactly such 

 groups, or that their arrangement is usually traceable thereto, 



* De Meijere, ' Over de haren der Zoogdieren in 't byzonder over liunne 

 wijze van raugscLikkiug,' Dissert. Amsterdam, 1893. 



t The important occiuTence of three hairs behind scales in mice has 

 already been pointed out by Jeutink in the memoir previously quoted 

 (Zoolog. Ergebnisse, iii, p. 81). 



