CATALOGUE. 61 
Although there appears to be a constant difference in 
size,* yet it will be seen by the preceding list that specimens 
of the same species differ as much in size as the so-called 
var. Virginicus differs from Charadrius fulvus. 
63. AGIALITIS SEMIPALMATUS, (p.) Cab. 
(RINGNECK.) 
An-abundant species during the migrations. Some prob- 
ably breed, as I found it common in July. 
64. AGIALITIS MELODUS var. CIRCUMCINTA, Ridg. 
(PIPING PLOVER.) 
An abundant species. I procured immature birds in July, 
and Mr. Perham found it breeding in June. This, I believe, 
is the most northern record of its capture, but future 
research, I think, will reveal that it has a much more 
northern range than naturalists generally suppose. Dur- 
* Not greater than would be caused by climatic influences and geographical dis- 
tribution. 
