Swallow Feb. 27. Mar. 3. Mar. 5. Mar. 25. Ap. 5. Ap. 15. Sand Martin Ap. 3. Ap. 5. Ap. 8. Ap. 12. Ap. 25. Ap. 25. House Martin Ap. 10. Ap. 15. Ap. 16. Ap. 20. May 1. May 1. Swift Ap. 15. Ap. 18. Ap. 20. Ap. 23. Ap. 30. May 3. The spring tide of migration appears to set in along the entire coast-line of the Mediterranean, and in a direction almost due north. I do not remember to have seen any record of the occurrence of the Martin on the west coast of Africa, although there seems to be no reason why it should not accompany the Swallow there in winter. Both species will rear two broods in a season; and this fact, doubtless, will account for the prolonged stay in autumn of the later fledged birds, which are not sufficiently strong on the wing to join the main body of emigrants at the usual time of their departure. [Illustration: SAND MARTIN] THE SAND MARTIN. (_Cotyle riparia._) This little bird has a much more extensive range than either of the foregoing species, being found in the New as well as in the Old World. In British North America M. Bourgeau obtained both birds and eggs on the Saskatchewan plains. Dr. Coues met with it in Arizona, and Professor Baird has recorded it from California. He says: “It furnishes almost a solitary instance amongst land birds of the same species inhabiting both continents permanently, and not as an accidental or occasional visitor in either.”[72] Mr. H. E. Dresser found it common in Southern Texas, and Mr. O. Salvin obtained several specimens in Guatemala. It has even been met with in the Bermudas, 600 miles from Cape Hatteras, the nearest point of the North American coast.[73]