TACHYCINETA THALASSINA, VIOLET-GEEEN SWALLOW. 87 



Hal). — Middle and Western Provinces. North to British America. South through 

 Mexico to Guatemala. 



List of sjoecimens. 



19208 

 19210 

 19211 

 19350 

 19351 



WindEiver.. . 



do 



do 



G. Bull Creek. 

 do 



May 26, 18G0 



do 



do 



June 7, ISeO 

 June 5, 1860 



F. V. Hay den. 

 do 



do 



G. H. Trook.. 

 do 



Not obtained by Lieutenant Warren's Expedition. 

 Later Expeditions. — 61665, Utah. 



A fine series of this lovely Swallow was procured by Captain Eay- 

 nolds, and its eggs are also in tbe collection. The locality is apparently 

 at about the northeast limit of distribution of the species. It does not 

 appear to be recorded north of Washington Territory and Vancouver. 

 In winter it retires beyond the United States, reaching to Guatemala. 

 Its breeding range appears to comprise all suitable localities in that por- 

 tion of the United States it occupies, as well as parts of Mexico ; to the 

 southward, it chiefly occupies elevated and wooded situations. 1 found 

 it abundant in the Eaton Mountains of New Mexico, in June ; it was 

 then doubtless breeding. In Arizona, as I have already recorded [1. c), 

 it is very abundant, being the characteristic Swallow of the piue regions, 

 where it breeds ; it arrives at Fort ^Yhipple about the 20th of March, 

 and remains until late in September. Dr. Cooper noticed its arrival in 

 the Santa Clara Valley, California, as early as March 15th, and further 

 observes that it "frequents chiefly the groves of oaks along the sides of 

 the valleys and across the whole coast range, excepting the windy and 

 cold neighborhood of the sea. They range at least as far north as the 

 Straits of Faca, and across the interior to the eastern base of the Eocky 

 Mountains." Dr. Suckley rei)orts its arrival at Paget Sound about the 

 10th of May. Mr. Allen found it iu July and August, in Colorado, in 

 the Garden of the Gods, about Castle Eock, and at Lake Pass. 



A well known and often recorded jjoint in the economy of the Swal- 

 lows, is the readiness with which thej' modify their ways of nesting ac- 

 cording to circumstances. Those species, like the Barn Swallow, the 

 White-bellied and Cliff Swallows, and the Purple Martin, which inhabit 

 populous countries, have almost completely changed their modes of nid- 

 ification, now breeding in the convenient places afforded by buildings, 

 or in shelters expressly provided for their use. In the case of the Cliff 

 Swallows, the change is of very recent date, and many records are pre- 

 served of the precise time when, in particular localities, the birds de- 

 serted cliffs to build under eaves, or when, adopting this habit, they 

 appeared and bred in places where they were before unknown. With 

 the Purple Martins the modification occurred earlier, and I am not aware 

 that the time is recorded. But in the west both these birds still adhere 

 to their primitive ways. Along the Missouri I saw great numbers of 

 nests of Cliff Swallows stuck in batches on the high vertical water- 

 worn exposures ; and in Arizona the Martins occupied the blasted tops 

 of tall pine-trees, in colonies, having driven off the Woodpeckers, right- 

 ful proprietors of the holes that riddled the trunks. It becomes an 

 interesting speculation whether the Bank Swallow will ever abandon its 

 burrows, and so far modify its fossorial nature as to build in chinks and 

 crannies, or affix a nest anywhere about a building. As far as is now 

 known, the Violet-green Swallow retains its primitive habits, but the 

 same easy adaptability to varying circumstances may be observed in 

 this case, warranting the inference that before long it will accept the con- 

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