36 Zoologia: N. Y. Zoological Society. [Vol. I 



mental biology has developed to a point where it can clearly 

 account for, if not indeed anticipate, results of experiment upon 

 wild creatures, there seems no more objection to admitting such 

 evidence than that obtained through embryology, anatomy or 

 palaeontology. The development of birds from a reptile-like type 

 is not the less certain because we know of only two specimens 

 of Archaeopteryx ; and, although comparatively few types of liv- 

 ing organisms can be experimentally tested, the resultant evi- 

 dence, when we can clearly interpret it, is of none the less value. 



The crucial point seems to be that, while we should use this 

 evidence to the utmost in unraveling the intricate processes of 

 evolution, and in understanding the past history of the wild 

 living forms, or as we call them species and subspecies, as now 

 defined — yet to alter our entire list of species, discarding all 

 forms — which are ontogenetically interchangeable under experi- 

 mentation or in a new environment, by analysis or synthesis as 

 the case may be, is no more reasonable than to discard a genus 

 of living creatures because palaeontology reveals more delicate 

 gradations between it and a second living group — isolated by the 

 present conditions of life. 



If I take an individual inca which, under certain conditions, 

 has changed to a darker form, more extreme than ridgwayi, and 

 apply to it the term nigra, I may claim that it represents a good 

 ontogenetic species, isolated by moult from any other species. 

 As long as the conditions remain the same, my new species re- 

 mains unchanged, perhaps for years, but if it moults into a still 

 blacker form, the status of nigra would revert, theoretically, to 

 the condition of an extinct fossil link; but practically, this dis- 

 tinction would be inimical to the usefulness of classification. 

 It would mean recognizing one of the past moults of the indi- 

 vidual as a prototype or ancestral connecting link! 



The boast of our scientific nomenclature is that it is as near 

 the natural order of evolution as possible and yet remain a help 

 to working naturalists. When this most important function is 

 imperilled by the naming of innumerable variations within a 

 narrow field, the more conservative biologists rightly protest. 

 The same would result if, in the case of Scardafella, having 

 transmuted an individual inca into ridgivayi, and thus proving 

 the differentiation to rest merely upon ontogenetic characters, 

 the name ridgwayi should be stricken from our lists, regardless 

 of the fact that there is apparently a geographical hiatus be- 

 tween the two forms in a wild state. Differences between the 

 two species in habits, nidification, courtship or notes, could not 

 be expressed were both swamped under one name. 



