46 



NORTH AMERICAN FAUNA 

 Measurements of Amazilia yraysoni and A. cinnamomea. 



lache lawrencei Ridgway. Lawrence's Humming Bird. 



Circe latirostris Graysou, Proc. Boston Soc. Nat. Hist., XIV, p. 282, 1871. 

 lache lawrencei (Berlepsch, Ms.) Ridgway, Man. N. Am. Birds, p. 320, 1887. 



Like the preceding species this is a common and generally distrib- 

 uted bird, and was found on all the islands. Like Grayson's hum- 

 ming birds, they were common about the flower garden at the custom 

 house on Maria Madre. Colonel Graysou found its nest on Maria 

 Madre and describes it as follows: "The elegant little structure I 

 found attached to a slender twig, and shaded with its leaves, about 

 5 feet from the ground. The situation was fronting the sea, but a few 

 paces from the water's edge, where the first beams of the morning sun 

 dissolved the dews. Its form is cup shaped, and composed of the down 

 of the silk cotton tree (Eriodendron) intermingled with the down of 

 <TEner plants and spider webs, the whole exterior neatly studded with 



Diminutive lichens; it contained two newly hatched young, but little 



larger than flies." 



In general appearance lache lawrencei closely resembles I. latirostris. 1 

 The dorsal surfaces of the males are nearly the same color, but the 

 upper tail coverts of lawrencei are grayish instead of green, as in lati- 

 rostris; their lower surface is a darker, duller green; the blue-throat 

 patch is nearly obsolete and replaced by an extension of the green of 

 the neck; the under-tail coverts are darker brown. 



The females of lawrencei differ mainly from those of latirostris in the 

 clearer, brighter green of the dorsal surface and darker under-tail 

 coverts. As the differences between the two birds seem to be fairly 

 constant, although not very striking, it is perhaps advisable to treat 

 them as species until more material proves the contrary. 



The type of I. latirostris formed part of the Bullock collection and 

 probably came from the southern end of the table-land near the Valley 

 of Mexico. The following measurements show the differences in size : 



1 lache latirostris undoubtedly occurs on the islands as a straggler. About midway 

 on our return to the coast a hummer passed close to the side of the boat, coming 

 from the direction of San Bias and heading in a direct line for the islands. As this 

 wanderer passed I had a close view and identified it as /. latirostris. 



