44 



NORTH AMERICAN FAUNA. 



face. The following averages show the relative size of graysoni and 

 sinalotnsis : 



Measurements of Dryobates a. graysoni and Dryobates .s. sinaloensis. 



An adult female in the National Museum collection from Mazatlan, 

 while having the normal bill and tarsus of sinaloensis, agrees with 

 birds from the Tres Marias in its long wings and tail. Its measure- 

 ments are as follows: Wing, 96; tail, 60; culmen, 18.5; tarsus, 16.5. 



Nycticlromus albicollis insularis Nelson. Tres Marias Parauque. 



Nyctidromus albicollis Grayson, Proc. Boston Soc. Nat. Hist. XIV, p. 273, 1871 ; 



Lawr., Mem. Boston Soc. Nat. Hist., II, p. 291, 1874. 

 Nyctidromus albicollis insularis Nelson, Proc. Biol. Soc. Washington XII, p. 9, 1898. 



On the mainland the parauques are rarely seen while the sun is 

 above the horizon, but when night falls they come out of the dense 

 thickets where they have passed the day and sit in dusty trails and 

 other open places. On Maria Madre they were among the commonest 

 birds frequenting old log roads through the forest and shady canyon 

 bottoms until late in the morning and coming out again at 3 or 4 o'clock 

 in the afternoon. Of late years these places have been so completely 

 given over to solitude that when a human being chances to stray into 

 them he is looked upon with little fear. The wood folk seem to con 

 sider him harmless and only a strange creature of their own kind. 



Parauques were among the most confiding birds found in these quiet 

 retreats and permitted a close approach before taking wing and moving 

 away. In the early dusk they were frequently seen hawking for insects 

 among the low trees. Several came about camp at the north end of 

 Maria Madre just after sunset, and flew very swiftly back and forth 

 with the same erratic course and vigorous wing strokes that are so 

 characteristic of the night-hawk. In fact, I mistook one of these birds 

 for a night hawk until it was secured. Their notes remind one slightly 

 of the whip-poor-will's, but are not so loud and far-reaching. The 

 regular call is made up of two and sometimes three syllables, besides 

 which they have various little clucking and purring notes. 



Curiously enough the parauques of the Tres Marias bear a much 

 greater resemblance, in size and color, to X. albicollis merrilli of the 

 Eio Grande Valley than to the ordinary birds of the adjacent mainland. 



