3.28 ]\rr. P. R. Lowe on Coloration as a Factor in 



was that the brilliant scarlet of its underparts was 

 apparently confused with the scarlet inflorescence of 

 certain arboreal and parasitic plants which were common. 

 The Trogon had, in fact, unconsciously "adapted itself*' 

 to its scarlet-tinted surroundings ; for it is to me quite an 

 unthinkable proposition to suppose that these scarlet- 

 coloured epiphytes could by any conceivable means have 

 so affected the germ-cells of these Trogons that they were 

 induced to respond in sympathy with their environment. 

 Yet this is exactly what we are often asked to believe. On 

 the contrary, the germ-cell produced the scarlet area and 

 the Trogon has made, so to speak, the best of a bad job. 



(3) The constancy and persistence of colour-pattern. 



I have already referred incidentally to this in the case of 

 the Ringed Plovers, in which we find that in spite of extreme 

 isolating conditions and of differences in the type of environ- 

 ment, the fundamental colour-pattern remains the same. 

 Not only is it persistent, but it is more constant than the 

 structural features of the bills, in which we find a whole 

 series of intergradations. 



There is another example in the case of three distinct 

 genera of Cuckoos from the East Indies, viz. Dryococcyx 

 from Celebes, Rhinococcyx of Java, and Urococcyx from 

 Sumatra and the Malay Peninsula. I have taken these 

 examples from Mr. Witmer Stone's paper, and it will be 

 noticed that while there are very distinct structuial differ- 

 ences in the form of the nostril corresponding to the three 

 o-enera, the colour-pattern remains the same. It seems to 

 me quite inconceivable that this colour -pattern owes its 

 origin to adaptation with environment, since if we com- 

 pared the immediate environment of East Indian with, let 

 us say. West Indian Cuckoos, the details would almost 

 certainly be found to be so completely similar that we 

 should expect to find a similarity of colour-pattern and 

 colour-tones, which however and in fact we do not. 



We have another instance in the series of the 'larger 



