XIV TABLE OF CONTENTS. 



Page. 



Genus 4. Nyctidromus Gould 535 



Key to the Species and Subspecies of Nyctidromus 536 



18. JS^yctidromus albicollis albicollis (Gmelin) 537 



19. Nyctidromus albicollis yucatanensis Nelson 543 



20. Nyctidromus albicollis sumichrasti Ridgway 543 



21. Nyctidromus albicollis nelsoni Ridgway 544 



22. Nyctidromus albicollis insularis Nelson 545 



23. Nyctidromus albicollis merrilli Sennett 546 



Genus 5. Phalsenoptilus Ridgway 547 



24. Phalsenoptilus nuttallii nuttallii (Audubon) 548 



25. Phalaenoptilus nuttallii californicus Ridgway 552 



Genus 6. Otophanes Brewster 553 



26. Otophanes mcleodii Brewster 554 



Genus 7. Nyctagreus Nelson 556 



27. Nyctagreus yucatanensis (Hartert) 557 



Genus 8. Chordeiles Swainson 559 



Key to the Species and Subspecies of Chordeiles 560 



28. Chordeiles virginianus virginianus (Gmelin) 5G2 



29. Chordeiles virginianus hesperis Grinnell 567 



30. Chordeiles virginianus sennetti (Coues) 568 



31. Chordeiles \'irginianus howelli Oberholser 570 



32. Chordeiles virginianus henryi (Cassin) 572 



33. Chordeiles virginianus aserriensis Cherrie 673 



34. Chordeiles virginianus chapmani (Coues) 574 



35. Chordeiles virginianus vicinus Riley 575 



36. Chordeiles virginianus minor (Cabanis) 576 



37. Chordeiles acutipennis micromeris Oberholser 577 



38. Chordeiles acutipennis inferior Oberholser 580 



39. Chordeiles acutipennis texensis (Lawrence) 581 



Family Nyctibud^. The Potoos 583 



Genus 1. Nyctibius Vieillot 584 



Key to the Species and Subspecies of Nyctibius 586 



1. Nyctibius grandis (Gmelin) 587 



2. Nyctibius griseus jamaicensis (Gmelin) 589 



3. Nyctibius griseus mexicanus (Nelson) 592 



4. Nyctibius griseus costaricensis Ridgway 593 



5. Nyctibius griseus panamensis Ridgway 593 



Suborder Striges. Owls 594 



Key to the Families of Striges 598 



Family Tytonid^. The Barn Owls 598 



Genus 1 . Tyto Billberg 600 



Key to the Species and Subspecies of Tyto 601 



1. Tyto perlata furcata (Temminck) 602 



2. Tyto perlata lucayana Riley 604 



3. Tyto perlata pratincola (Bonaparte) 605 



4. Tyto perlata guatemalae (Ridgway) 610 



5. Tyto bargei (Hartert) 611 



6. Tyto glaucops (Kaup) 612 



7. Tyto insularis insularis (Pelzeln) 613 



8. Tyto insularis nigrescens (Lawrence) 615 



9. Tyto punctatissima (Gray) 616 



Family Bubonid^. The Eared Owls 617 



Key to the American Genera of Bubonidae 619 



