180 Mr. P. R. Lowe on [Ibis, 



In Podiceps cristatus infasratus, as pointed out by 

 Mr. Claude Grant (Ibis, 1915, p. 51)', the white superciliary 

 streak present in P. c. cristatus (Europe) is absent in the 

 African race, a character which is as noticeable in winter as 

 in summer dress. This is well illustrated in a woodcut 

 accompanying the article. 



Querquedida discors allrinucha is similar to Q. d. discors 

 except that, in the nuptial plumage of the male, the cres- 

 centic white patch in front of the eye is continued over the 

 eye in a thin superciliary line down to the nape, where it 

 meets the line from the opposite side to form a white nuohal 

 patch. 



This Teal breeds commonly in Louisiana, possibly as 

 far east as Florida, also in Texas and Mexico, and 

 begins nesting before the Blue-winged Teal departs for 

 the north. 



A good illustration is given in the reference quoted above. 



In these examples, then, we find that the race, variety, or 

 subspecies — call it what you will — differs from the typical 

 species in the presence or absence of well-nuirked colour- 

 pattern characters. We find that certain qualitative changes 

 or characters have been introduced. The iact that they are 

 small differences does not matter in the least ; for tlie 

 important point about them is that they are definitely and 

 obviously heritable characters, which, by no stretch of the 

 imagination, can be conceived of as co-related with adap- 

 tation. 



The case of the Louisiana Teal is particularly interesting, 

 as the character has apparently not as yet been completely 

 and permanently established. To be so definitely and con- 

 cisely repeated in succeeding generations there is only one 

 conceivable way by which such characters could have 

 originated ; there must have been some change, some 

 " i^gS^^^y " — ^^^^ ^^ what you will — initiated de novo in the 

 chromosomes or chromomeres, or at au}^ rate in the fertilised 

 ovum. Moreover, for the continued presence, or the con- 

 tinued absence, of such mutational characters in such 

 differentiated races the only possible explanation would 



