1894.] NEW-YORK MICROSCOPICAL SOCIETY. 51 



may or may not take part, and those developing from a purely 

 epidermal source. Fish scales and derm denticles are examples 

 of the former ; in the lower types they forni a complete exo- 

 skeleton ; but as we ascend in the animal scale it is found that 

 as the endo-skeleton becomes more highly developed this exo- or 

 dermal skeleton grows of less and less importance, until finally 

 it disappears altogether. Epidermal structures (hairs, feathers, 

 e.g.) have now become of greater value. It seems that with the 

 higher development of the internal skeleton and the degenera- 

 tion of dermal structures the epidermal derivatives have grown 

 in importance. 



Scales, feathers, and hairs are undoubtedly derived from a 

 more primitive, common condition, for in their individual devel- 

 opments they show many points of resemblance. The interme- 

 diate form between reptile-scale and bird-feather has not as yet 

 been found ; but feather and hair both point to one antecedent 

 type, found at the present day in the spurs of birds and the hair 

 of Monatremes. For in Echidna we find a hair without any 

 medullary substance, and then succeeding stages to typical hair. 

 The spur is very likely descended fronj a hair with a thickened 

 outer layer. This structure may break up into rays and form a 

 feather, or become flattened out to form a scale. 



The relations of these structures to each other have furnished 

 material for many theories, but we still await the final and defi- 

 nite settlement of the question. This is but one of the many 

 problems which constitute such a fascinating field of research to 

 the modern biologist, who can accomplish wonders if he would 

 but attempt to elucidate and harmonize, or else disprove and 

 expunge, some of the many theories of his predecessors regarding 

 these questions. 



IN MEMORIAM. 



REV. SAMUEL LOCKWOOD, PH.D. 



Dr. Lockwood died at his residence. Freehold, N. J., on Janu- 

 ary 9th, 1894, in the seventy-fifth year of his age. 



He was born at Mansfield, England, on January 20th, 1819, 

 and was brought in his infancy to New York City, where he re- 

 ceived his education, graduating from the New York University 



