Vol 



X VT 



'^^'f^ Rcroit Li'/rni/ii rr. 207 



Merriam sliows tlial tlierc aic si ill possibilities in hotli lines, ami that her 

 book is not without raisoit (/'?/rr. It is adniirablj adapted as 'A Bird 

 I?ook for Beginners," anti \\ e trust it will achieve the success it so well 

 merits. — J. A. A. 



Hair and Feathers.' — Professor Kingsle}- here reviews recent investiga- 

 tions regarding the development and structure of hair and feathers, no- 

 tably those published in Germany, of which he presents a brief summary. 

 lie makes special acknowledgment to the recent able review of the sub- 

 ject bv Professor Keibel, in Merkel and Bonnet's 'Ergebnesse der Anato- 

 mie und Entwickelungsgeschichte,' 1896. As is now well known, hair and 

 feathers are not only unlike in structure and appearance, but in method of 

 origin and growth. "According to Davies all contour feathers are pre- 

 ceded by doNvn-feathers," or, in other words, "the germ of the definitive 

 feather is a direct derivative of the germ of the down-feather." The 

 process of formation is described at some length, concluding as follows : 

 " With the withdrawal of the pulp from the feather there is no longer 

 any nerve or blood supply to the parts of the feather. The cells of which 

 it is composed are dead and dry so that it seems impossible that any 

 change can take place in it. The whole question of change in color of 

 the fully formed feather was recently reopened by Mr. J. A. Allen who 

 maintained that, once formed, the feathers do not change in their mark- 

 ings. The whole history of development seems to afford him full support. 

 Yet this year [1897] the attempt has been made to show that feathers do 

 change in their markings. In this, as the matter now stands, the burden 

 of proof is upon those who support the possibility of change." 



Regarding the origin of hair and feathers, reference is made to the old 

 view that they were of homologous origin, and that both were derived 

 from the reptilian scale. "It may be said, however," says Kingslev, 

 " that Davies, to whom we owe the most accurate account of the develop- 

 ment of the feather declines to regard pin-feathers [filoplumes.?] as the 

 simplest type of the avian tegumentary covering but rather as a retro- 

 grade condition ; and farther, that he regards the scales upon the tarsal and 

 digital regions of birds as secondary formations, agreeing in this with 

 Jeffries." Again, "Maurer maintains that hair and feathers are not homo- 

 logous structures. The feather, according to his view has been derived 

 from the Reptilian scale while hair has arisen from the dermal sense 

 organs of the Ichthyopsida as a result of a change in habits and conditions 

 of life." A brief statement is given of Maurer's investigations and con- 

 clusions, and the reader is further advised to refer to Keibel's summary, 

 "with ifs bibliography of over one hundred titles." — J. A. A. 



Baur on the Birds of the Galapagos Archipelago. — Dr. Baur reiterates 



> Hair and Feathers. By J. S. Kingsley. Amer. Naturalist, Vol. XXXI, 

 Sept. 1897, pp. 767-777, figs. 1-14. 



