Fig. i. Helminthophila pinus, male. 



Fig. 2. Helminthophila pinus, female. 



Fig. 3. "Lawrence's Warbler," male; one of the integrating forms. 



Fig. 4. "Brewster's Warbler," male; another of the intergrading forms 



Fig. 5. Helminthophila chrysoptera, male. 



Fig. 6. Helminthophila chrysoptera, female. 



ii nrblers of North Ai 



