28 Trans. Acad. Sci. of St. Louis 
on February 21, 1927, a flock of about the same number was seen 
by Dr. . Allen. It is quite possible that these flocks may 
represent penident birds, however, for on February 21, 1927, 
nearly a foot of soft snow was on the ground and this flocking 
may have been a secondary reuniting of resident birds forced, 
temporarily, from their territories. Jones (1910), has noted 
that the Prairie Horned Lark refiocks after mating in the spring 
if severe weather modifies its breeding areas. The present writer 
noted that prolonged and deep snow at the end of March, even 
after nests had been started, caused the birds to desert their 
territories and to collect in groups along the roadsides at Evans- 
ton, Illinois. Even though this may account for some flocks in 
February and March it remains true also that Larks must pass 
over to reach breeding areas to the north and these very prob- 
ably do so in February and March after residents are established. 
Small flocks were noted at Evanston February 28, 1926, long 
after residents had come onto their breeding grounds, similarly 
a small flock of ten to twelve birds was flushed from a patch of 
Setaria at Ithaca, March 1. Again small flocks were noted once 
or twice in April at Evanston but these proved to be O. a. alpes- 
tris and not praticola (for which see under account of birds that 
fed over or on the subdivisions at Evanston, Illinois). 
Vagrants, immature or unmated birds appeared occasionally at 
Ithaca, New York in April, but since the mated males drove 
them out of the vicinity whenever they attempted to alight, it 
was impossible to ascertain their sex. It is possible, though 
improbable, that they represented young of successful March 
nestings. 
of migration of sexes and individuals—The fol- 
lowing very tentative categories of spring arrivals may be listed 
in summary in the order of their arrival: 
Resident adult males 
Resident adult females 
Transient males and females 
Vagrant, immature, etc. 
i oF: oe et 
