Loology. _ 1128 
The two species or geographical varieties, whichever they may be, 
are distinguished by certain peculiaritiés in their song. e eastern 
species, Sturnella magna, extends about two-thirds way across the 
State of Iowa, while the western form, S. neglecta, is found nearly 
as far east as the Mississippi River. At their extremes of distribu- 
tion both of the forms are easily recognized, and are typical exam- 
ples. But in the intervening region, where the two overlaps, as it 
were, the birds were not to be positively separated by note alone, a 
sight of the bird itself being generally necessary for positive identi- 
fication. Whether the variation in song was due to imitation of 
one by the other or to an actual intermingling of the two, he did not 
attempt to decide. In referring to the reason for the distribution 
of the two species, the agency of the glacial period was evoked. At 
the time when the ice reached its greatest extension southward, the 
waters of the Gulf of Mexico extended northward, forming a junc- 
tion with the ice and dividing the continent into an eastern and a 
western portion. The suggestion’ was made that if at a period 
anterior to the glacial epoch one species was widely distributed over 
the continent, the time that elapsed until the normal condition of 
the country was again reached was sufficiently long to allow dif- 
ferentiation to proceed, and two species or distinct varieties to be 
ormed. l 
In the discussion which ensued Dr. Cones took the ground that 
a very long period of times was not absolutely necessary for 
formation of new races, varieties or species: that environment or 
food often causes changes with considerable rapidity, and that it 
is probable new species, so-called, are being formed under changing 
conditions in our own day and in short periods of time. Dr. Mer- 
riam mentioned that changes in coloration are often due to change 
of food : that a breeder in Holland was so well known for his skill 
in “coloring up” Flamingoes, that these birds were sent to him 
from all parts of Europe. By some change in food, a secret known 
only to himself, he was enabled in a short time to restore them to 
full color. Yet in a short time the new color was lost and the 
original faded aspect resumed. Prof. C. V. Riley cited numerous 
instances of the distribution of insects similar to that of the meaaow 
larks. Dr. Gill called attention to similar cases with fishes. a 
may be well to note here similar parallel cases in the plant world. 
atis viorna is a well-known, widely distributed plant of east- 
ern North America, extending, however, only as far west as Kansas, 
where it is not common. C. pitcheri, classed by some as a variety 
of Viorna, is a western form found nowhere east of the lower 
Wabash valley in Indiana, but extending westward through Mis- 
souri, Arkansas and Texas. It is extremely probable that the two 
forms owe their distribution to the same cause or causes as the two 
forms of meadow lark above referred to. Some species of Verno- 
