124 Mr. C. H. B. Grant on Birds collected in Argentina y 
d,e. $ ? ad. Porto Esperan 5 a, Brazil. Oct. 13, 1909. 
f,g. $ ? ad. Colonia Mihanovitch, N. Argentine. Nov. 5, 
1909. 
Irides hazel ; bill, legs, and toes black. 
The November birds are shewing signs of wear and 
fading ; and the female on dissection was found to be 
laying. 
The December bird is starting to moult on the back, and 
the March bird is in full moult and has almost assumed the 
new feathering on the body. 
A rare visitor to the Ajo district, only four being observed 
there during both my visits. 
On the river expedition not many were seen altogether, 
though at Porto Esperan 9 a quite a number were about, which 
I think had only just arrived there. 
101. Milvulus tyrannus. 
Milvulus tyrannus Scl. Cat. B. xiv. p. 277; Arg. Orn. i. 
p. 160. 
a , b, c. S ? ad. Los Ynglases, Ajo. Oct. 21-27, 1908. 
d. $ ad. ,, ,, Jan. 7, 1909. 
e. $ ad. „ „ Jan. 19, 1910. 
/. <$ a( L Pan de Azucar, Brazil. Sept. 19, 1909. 
Irides hazel; bill, legs, and toes black. 
The Scissor-tailed Tyrant is a summer visitor to the Ajo 
district, making its appearance about October and leaving 
again towards April. 
The males appear to arrive first, followed soon after by the 
females, when breeding operations are commenced, the nest 
being almost invariably placed on the outside branches 
either of solitary trees or of those on the edge of the montes, 
generally in rather conspicuous positions and between from 
ten to twenty feet from the ground. The fabric is placed 
on some horizontal branch or in a fork ; it is cup-shaped in 
form, and composed of thistle-down, grass, and wool, the full 
clutch of eggs being four. 
As a rule, this bird is seen perched on wire fences or 
on the tops of plants in the open camp from which 
