No. 494J ZOOLOGICAL PROGRESS 



L33 



systems of artificial illumination are regarded by us as 

 one of the many evidences of advanced civilization and 

 yet our best products are ridiculously poor compared with 

 those of the lower animals. Gas or other such luinmants 

 yield at best something less than one per cent, light, the 

 remainder of the energy being dissipated as waste heat, 

 and our most successful means of illumination scarcely 

 reach fifty per cent, of efficiency. The radiant energy of 

 the luminous organ of a fire-fly is all light, and none is 

 wasted as heat. Were the processes of this organ under- 

 stood and made applicable to daily life, they would at once 

 sweep out of existence every illuminating plant known. 

 Such a revolution as this suggests awaits only the advance 

 of zoological science, and, as I have said, this may be 

 looked for in the near future. To my mind it affords one 

 of the brightest outlooks for zoological investigation. 



Thus far I have scarcely touched on what has been 

 for so long a time the rallying word in biological work, 

 evolution. But, if we knew the physiological workings of 

 the animal body, especially in relation to inheritance, etc., 

 evolution would be in large part understood and the lines 

 of work that have just been recalled would be only ex- 

 amples of evolutionary processes. The most promising 

 recent change in the study of evolution, a change which 

 we owe largely to de Vries, is the discovery that evolution 

 as now understood is probably going on before our eyes 

 and at a measurable rate; hence it is open to observational 

 and experimental treatment and we may expect renewed 

 and rapid growth in the near future for this line of work. 



Many of the unexplored regions touched upon m this 

 survey are of such magnitude that few can hope to be 

 their conquerors, but all may aid in preparing the way. 

 In invading these new regions former methods and means 

 will be sure to be found insufficient; the help of kindred 

 sciences, such as physics and chemistry, must be called 

 upon. This appears to be a sufficient answer to those who 

 thought that thev saw in the subdivision of zoology and 

 of other sciences a step away from the true unity of sci- 

 entific endeavor. 



