290 



its characteristic animal community. Figure 2, Plate LXVII and 

 Plate LXVIII show conditions in this series. Autumn weather has 

 been very diverse in character since the observations began. In No- 

 vember, 19 1 3, very unusual conditions, like those of early spring, 

 prevailed. The air was warm and balmy; the fields were green; 

 and flying insects were much in evidence. At this time, November 

 24, 19 1 3, a garter snake was captured on the high ground at the sta- 

 tion. It was very active, and it had just swallowed a large leopard 

 frog. 



The plant life of this prairie area is probably the most important 

 factor in determining its vertebrates, since it not only furnishes them 

 food, in the shape of seeds, fruits, roots, leaves, and insects, but also 

 affords them shelter, seclusion, and concealment while they are rest- 

 ing, feeding, and nesting. A few instances of these latter uses of 

 plants to vertebrates were observed : rabbits were found hiding among 

 the plants ; a king rail concealed itself so effectively in a small patch 

 of rushes that much searching did not reveal it; a red-winged black- 

 bird's nest was attached to rush leaves, which not only supported the 

 nest but concealed it (PI. LXIX, Fig. 2). 



Vertebrates were in all probability attracted to the station by in- 

 sects and other invertebrates which furnish them food, yet meager 

 data on this point was obtained, for few were seen feeding. A shrike 

 caught a monarch butterfly while being watched by the writer, and a 

 shrike which was killed contained many insect fragments, chiefly of 

 grasshoppers and other Orthoptera. Bronzed grackles were seen 

 searching for grubworms behind a harrow that was being used in 

 the field just east of Station I, May 21, 19 14. In fact, most of the 

 birds seen at the station were well-known insect eaters. 



Vertebrates have a marked influence on each other, and their 

 interactions have much to do with the character of the vertebrate 

 fauna at Station I. Few facts concerning these interrelations 

 could be obtained, however, because of the meagerness of the field 

 work done. A kingbird was seen chasing a marsh hawk over the 

 fields near the station; a red-winged blackbird appeared to be trying 

 to drive away a sparrow-hawk that was about the telegraph poles at 

 the station; and, as previously stated, a garter snake was found, 

 which had swallowed a large frog. Shrikes and sparrow-hawks seen 

 along the railroad here and elsewhere in winter are in all probability 

 hunting for mice. Man produces at this station a marked effect on 

 the vertebrates of a lower order than himself. During the hunting 

 season, hunters were often seen at the station or near it looking for 

 rabbits, bob-whites, or ducks; and judging from the many empty 

 shot-shells found lying on the ground, some game is found by gun- 



