CONTENTS. 



PAGE. 



PREFACE 5 



AN HISTORICAL AND EXPERIMENTAL STUDY OF HOMING 7 



Introduction 9 



Historical outline of the problem of homing 9 



Proximate orientation 11 



Distant orientation 11 



Habit theories 13 



Theories and experiments on the function of vision in homing 13 



Experiments showing importance of visual impulses in homing 15 



Evidence against Hachet-Souplet's theory based upon mathematical con- 

 siderations 16 



A theory based upon cutaneous sensibility 17 



Evidence against Cyon's "Spiirsinn Theorie" 19 



Reflex theories 20 



Reflex theories based on the functioning of semicircular canals 20 



Reflex theories assuming magnetic sensibility 21 



Experimental evidence against the reflex theories 23 



Information on Homing Pigeons gathered from practical fliers 25 



The record of a typical flight 27 



Data on the speed of the Homing Pigeon 28 



The problem of homing in bird migration 29 



Homing in the Frigate Bird 30 



Homing in other vertebrates 31 



History of the Tortugas Noddy and Sooty Tern colonies 35 



Resume of instinctive life of colonies 35 



Migration 36 



Feeding instincts 37 



Nesting activities of Noddies 38 



Nesting activities of Sooties 38 



Swimming and resting upon the water 39 



Tests upon the water habits and instincts of Noddy and Sooty Terns ... 39 



Retention of nesting habits 41 



Observation on behavior of bird left at nest after removal of nest mate . . 41 



Retention of nesting habits and nest locality in bird removed from nest . . 43 



General technique of the homing experiments 45 



Previous experiments on homing at Tortugas 46 



Record of experimental work on homing in 1910 and 1913 47 



The flight from Key West 47 



Attempted flight from New York and en route 49 



The first Galveston trip, 1910 50 



The first Mobile trip 51 



The second Mobile trip 52 



Notes of Mr. Lashley on the care of the birds during the Mobile trip ... 52 



Bird Key notes on the returns from the second Mobile tiip 54 



The second Galveston flight 54 



Returns to Bird Key from the second Galveston flight 56 



Bearing of the present studies upon the general problem of homing 59 



NOTES ON THE NESTING ACTIVITIES OF THE NODDY AND SOOTY TERNS 61 



Orientation in the nest locality 61 



Experiments with Sooties 63 



Recognition of the nest site 63 



The alighting place 70 



Experiments with Noddies 72 



The nest and perch 72 



Orientation in approaching the island 74 



Summary of work on nest recognition 75 



3 



