Birds from Coahuila, Mexico Part 13

*_Atlapetes pileatus dilutus_ Ridgway.--_Specimens examined:_ total 2: [Male] 32942 and [Female] 32943 from 13 mi. E San Antonio de las Alazanas, 9950 ft., July 6, 1955.

The Rufous-capped Atlapetes occurs uncommonly in southeastern Coahuila.

The male and female _A. p. dilutus_ from 13 mi. E San Antonio de las Alazanas represent the first records of occurrence of this subspecies in the State. The smaller size, grayer upper parts, and pale yellow color of the underparts of Nos. 32942-32943 characterize the subspecies _dilutus_. The size of the testes (76 mm.) of No. 32942 and the date (July 6) on which both specimens were collected indicate breeding by this species in Coahuila.

*_Arremonops rufivirgata rufivirgata_ (Lawrence).--_Specimens examined:_ total 2: [Male] 32152 and [Female] 32153 from 2 mi. S, 3 mi.

E San Juan de Sabinas, June 22 and 23, 1952.

The Olive Sparrow is uncommon in Coahuila. Miller, Friedmann, Griscom, and Moore (1957:349) listed _A. r. rufivirgata_ from Sabinas on February 10. Sabinas and southeast of San Juan de Sabinas seem to be the only localities in Coahuila where the Olive Sparrow has been collected and also are at the westernmost extremity of range of this species. The size of the testes (97 mm.) of No. 32152 and the dates of collection indicate breeding by the Olive Sparrow in Coahuila.

_Chlorura chlorura_ (Audubon).--_Specimen examined:_ one, [Male] 30238, from 1 mi. N San Lorenzo, 4200 ft., February 5, 1951.

The Green-tailed Towhee is a common migrant and winter visitant in Coahuila; the species has been found at several localities. Miller (1955a:175) noted several migrants "each day in the last week of April ... at the mouth of Boquillas Canyon" of the Sierra del Carmen.

Burleigh and Lowery (1942:207) noted the species "in an arroyo in the open desert country about twenty miles west of Saltillo on April 22."

Miller, Friedmann, Griscom, and Moore (1957:351) listed the Green-tailed Towhee from 12 mi. W Saltillo on September 28 and from Sabinas.

*_Piplio erythrophthalmus gaigei_ Van Tyne and Sutton.--_Specimens examined:_ total 3: [Female] 31102 from Fortin (=33 mi. N, 8 mi. W San Geronimo), 3300 ft., March 28, 1952, weight, 38.8 gms.; [Male] 35412 (skeleton only) from Sierra del Pino (=5 mi. W, 3 mi. S Acebuches), 6200 ft., May 15, 1954, testes enlarged, weight, 34 gms.; and [Male]

31593 from 17 mi. S Ocampo, 5300 ft., April 7, 1954, weight, 38 gms.

The Rufous-sided Towhee is locally common in Coahuila; _P. e. gaigei_ is present in northern Coahuila. Miller (1955a:175) remarked that "between 6800 and 7500 feet these towhees were spa.r.s.ely distributed in areas of scattered low ceanothus and hawthorne, chiefly in canyon bottoms, but also on slopes where ceanothus was intermingled with downed timber and young pines." He (_loc. cit._) indicated that the adult obtained by Marsh from Vivoras Canyon on August 25 was _P. e.

gaigei_ rather than _P. maculatus monta.n.u.s_ (see also Sibley, 1950:127). d.i.c.kerman saw Rufous-sided Towhees in the Sierra de la Madera on December 13, 1953. I have referred Nos. 31102 and 31593 to _gaigei_ although both are close to _orientalis_. The size of the testes (148 mm.) of No. 31593 suggests breeding.

*_Piplio erythrophthalmus orientalis_ Sibley.--_Specimens examined:_ total 3: [Male] 32154 from 7 mi. S, 4 mi. E Bella Union, 7200 ft., June 25, 1952; [Male] 33223 (skeleton only) from 13 mi. E San Antonio de las Alazanas, 9950 ft., July 6, 1955; and [Male] 31630 from Mesa de Tablas, 8600 ft., January 15, 1954, weight, 46 gms.

This subspecies of the Rufous-sided Towhee occurs in southeastern Coahuila. Burleigh and Lowery (1942:207) stated that it "was limited in its distribution to the mountain sides ... [and was] noted in the arroyos at the base of the mountains and from there up to about 8,000 feet." These authors identified their specimens from Diamante Pa.s.s and from Saltillo as _Pipilo maculatus gaigei_. Sibley (1950:129) reidentified them, as well as a series from Sierra de Guadalupe, as _P.

e. orientalis_. The size of the testes (127 mm.) of No. 32154 as well as the date (June 25) on which it was obtained suggests breeding by the Rufous-sided Towhee in southeastern Coahuila.

*_Pipilo fuscus potosinus_ Ridgway.--_Specimens examined:_ total 3: [Male] 32155 from 7 mi. S, 4 mi. E Bella Union, 7200 ft., June 25, 1952; [Male] 31676 from the west foot of Pico de Jimulco, 5000 ft., April 5, 1953, weight, 45 gms.; and s.e.x ? 29560 from 7 mi. S, 1 mi. E Gomez Farias, 6500 ft., November 19, 1949, weight, 46.5 gms.

The subspecies _potosinus_ has been recorded from several localities in Coahuila. Davis (1951:70) listed the following localities in the State from which _P. f. potosinus_ has been collected: Muralla, San Lazaro Mountains, 50 mi. S Monclova, 2850 ft., Saltillo; Saltillo (Chorro de Agua); 19 mi. W Saltillo; Cresta Blanca, 12 mi. W Saltillo, 5500 ft.; Diamante Pa.s.s, 11 mi. S Saltillo, 6000-8000 ft.; and Carneros. Miller, Friedmann, Griscom, and Moore (1957:358) recorded a "small juvenile"

from El Diamante on July 5. Sutton and Burleigh (1939a:45) recorded _P.

f. texa.n.u.s_ from Diamante Pa.s.s on March 6. I suspect that Davis (_op.

cit._) reidentified the specimen concerned from Diamante Pa.s.s as _P. f.

potosinus_. Burleigh and Lowery (1942:207) indicated that _P. f.

potosinus_ "was fairly common and of general distribution in the area, occurring both on the arid plateau about Saltillo and on the mountain sides up to an elevation of about 8,000 feet." Nos. 32155, 31676, and 29560 are typical for _P. f. potosinus_. The size of the testes (147 mm.) of No. 32155 suggests breeding by the Brown Towhee in southeastern Coahuila.

*_Pipilo fuscus texa.n.u.s_ van Rossem.--_Specimen examined:_ one, [Female] 31103, from 10 mi. S, 5 mi. E Boquillas, 1500 ft., March 5, 1952, weight, 46.9 gms.

This subspecies of the Brown Towhee occurs in northwestern Coahuila south through the Sierra del Carmen. Miller (1955a:176) reported that his series of Brown Towhees from the Sierra del Carmen agreed satisfactorily with _texa.n.u.s_ although revealing some sign of intergradation with _potosinus_. Davis (1951:70) thought that _P. f.

potosinus_ is present in northern as well as southern Coahuila. Miller (1955a:176), however, remarked that _P. f. texa.n.u.s_ is more characteristic of the population of Brown Towhees of northwestern Coahuila. He indicated that a single juvenile taken by Marsh on August 28 from Jardin del Sur and allocated to _P. f. potosinus_ by Davis probably is _P. f. texa.n.u.s_.

_Calamospiza melanocorys_ Stejneger.--_Specimen examined:_ one, [Male]

30239, from 10 mi. E Torreon, 3700 ft., January 9, 1951.

The Lark Bunting is an uncommon winter visitant in Coahuila. Other than the present specimen, the only record of the Lark Bunting in Coahuila is that of Burleigh and Lowery (1942:207), who reported a small flock of this species from which several specimens were collected "on April 20 in a field on the edge of Saltillo."

_Pa.s.serculus sandwichensis oblitus_ Peters and Griscom.--Miller, Friedmann, Griscom, and Moore (1957:364) recorded _P. s. oblitus_ from Sabinas on February 25 and March 18 and 24. These records represent spa.r.s.e winter visitants to Coahuila.

_Pa.s.serculus sandwichensis brooksi_ Bishop.--Burleigh and Lowery (1942:208) recorded _P. s. brooksi_ from Diamante Pa.s.s in April; Miller, Friedmann, Griscom, and Moore (1957:363) remarked that this specimen is perhaps best regarded as a variant of one of the races normally wintering in this area.

_Pa.s.serculus sandwichensis anthinus_ Bonaparte.--_Specimens examined:_ total 3: [Male] 31104 from 10 mi. E Hacienda La Mariposa, 2000 ft., March 30, 1952, weight 15 gms.; [Female] 31105 from 8 mi. N, 4 mi. W Muzquiz, 1800 ft., April 1, 1952, weight, 19.0 gms.; and [Female] 31594 from 17 mi. S Ocampo, 5300 ft., April 7, 1954, weight, 16 gms.

Burleigh and Lowery (1942:208) recorded _P. s. anthinus_ from Diamante Pa.s.s. This subspecies is not uncommon in Coahuila. The University of Kansas specimens showed no indication of breeding.

_Pa.s.serculus sandwichensis nevadensis_ Grinnell.--This subspecies of the Savannah Sparrow is uncommon in Coahuila; h.e.l.lmayr (1938:490) listed one specimen from Sabinas.

_Pa.s.serculus sandwichensis brunnescens_ (Butler).--Burleigh and Lowery (1942:208) recorded this subspecies of the Savannah Sparrow from Diamante Pa.s.s in April.

_Ammodramus savannarum perpallidus_ (Coues).--_Specimen examined:_ one, [Female] 31562, from 3 mi. N, 4 mi. E San Francisco (=25 mi. N Ocampo), 4850 ft., May 16, 1954, weight, 15 gms.

The Gra.s.shopper Sparrow is an uncommon spring and possibly fall migrant in Coahuila. Miller, Friedmann, Griscom, and Moore (1957:367) recorded _A. s. perpallidus_ from Sabinas on March 12. No. 31562, which was obtained in a yucca and acacia a.s.sociation, had little fat.

_Ammodramus bairdii_ (Audubon).--Miller, Friedmann, Griscom, and Moore (1957:368) remarked that Baird's Sparrow is a rare winter visitant to the northern states of Mexico and recorded _A. bairdii_ from Saltillo on May 8.

_Pooecetes gramineus confinis_ Baird.--The Vesper Sparrow seems to be an uncommon winter visitant in Coahuila. Miller (1955a:176) found _P.

g. confinis_ "on two occasions in the gra.s.s of the dry cienega at the head of Corte Madera Canyon at 7500 feet" on April 9 and 14 in the Sierra del Carmen. In April, Burleigh and Lowery (1942:208) found _P.

g. confinis_ only in Diamante Valley where this sparrow "appeared to be quite uncommon." Sutton and Burleigh (1939a:45) took a male _P. g.

confinis_ at San Pedro on January 29.

*_Chondestes grammacus strigatus_ Swainson.--_Specimen examined:_ one, [Male] 32156, from 8 mi. N, 2 mi. W Piedras Negras, June 18, 1952.

The Lark Sparrow is not uncommon in Coahuila. Miller (1955a:176) saw one male, "apparently on a breeding territory, on April 27 in an open, rather barren desert flat adjoining the lower part of Boquillas wash at 4600 feet." He reported that Marsh took a young of the year, still largely in juvenile plumage, on September 6 in the Sierra del Carmen.

Amadon and Phillips (1947:580) remarked that Lark Sparrows were common "about Las Delicias" after August 18. Findley saw Lark Sparrows 2 mi. W Jimenez on June 19, 1952, and 2 mi. S and 11 mi. E Nava on June 15, 1952. d.i.c.kerman saw Lark Sparrows at San Marcos on May 4, 1954. The pale and narrowly streaked upperparts of No. 32156 are typical for _C.

g. strigatus_. The size of the testes (94 mm.) of No. 32156 and the date (June 18) on which it was obtained suggest breeding by the Lark Sparrow in northeastern Coahuila.

*_Aimophila ruficeps tenuirostris_ Burleigh and Lowery.--This subspecies of the Rufous-crowned Sparrow is resident in the northern part of Coahuila. Miller (1955a:176) remarked that the species "ranged up to 7000 feet on open south-facing slopes within the oak belt" of the Sierra del Carmen. Specimens collected by him showed no approach to _boucardi_ of southern Mexico and seem to be closest to _tenuirostris_.

Miller referred the specimen that Marsh and Stevenson (1938:287) took on August 22 in Chuperosa Canyon to _tenuirostris_ rather than _boucardi_. Miller, Friedmann, Griscom, and Moore (1957:376) listed _A.

r. tenuirostris_ from 50 mi. S Monclova on November 8 and 10.

*_Aimophila ruficeps boucardi_ (Sclater).--This subspecies of the Rufous-crowned Sparrow is common in southern Coahuila. Burleigh and Lowery (1942:208) indicated that _A. r. boucardi_ was common throughout the mountainous areas and to some extent in the arroyos of the open desert country of southeastern Coahuila. Sutton and Burleigh (1939a:46) took a female _A. r. boucardi_ "near Diamante Pa.s.s." Ridgway (1901:252) listed _A. r. boucardi_ from Carneros. _A. r. tenuirostris_ and _boucardi_ seem to intergrade in central and even southern Coahuila.

Miller, Friedmann, Griscom, and Moore (1957:376) recorded intermediate populations of the Rufous-crowned Sparrow from 12 mi. W Saltillo.

*_Aimophila ca.s.sinii_ (Woodhouse).--_Specimens examined:_ total 2: [Male] 32157 from 9 mi. S, 11 mi. E Sabinas, June 14, 1952; and [Male]

32158 from 18 mi. S, 14 mi. E Tanque Alvarez, 4000 ft., July 6, 1952.

Ca.s.sin's Sparrow seems to be common in Coahuila. The AOU Check-list Committee (1957:603) listed _A. ca.s.sinii_ from 10 mi. E Saltillo.

Miller, Friedmann, Griscom, and Moore (1957:378-379) recorded Ca.s.sin's Sparrow from Sabinas, on April 25; from 25 mi. SW Monclova, on November 20; from 12 mi. W Saltillo, on September 28; and from 10 mi. NE Saltillo, on July 3. These authors stated that Ca.s.sin's Sparrow was breeding 10 mi. NE Saltillo. The sizes of the testes (53 mm.; 75 mm.) of Nos. 32157-32158, respectively, and the dates (June 14, July 6) on which they were obtained are additional evidence of breeding by Ca.s.sin's Sparrow in Coahuila.

*_Amphispiza bilineata bilineata_ (Ca.s.sin).--_Specimens examined:_ total 5: [Male] 32159 and [Female] 32163 from 2 mi. W Jimenez, 850 ft., June 20, 1952; [Male] 32160 from 8 mi. N, 2 mi. W Piedras Negras, June 18, 1952; [Male] 32161 and s.e.x ? 32162 from 5 mi. N, 19 mi. W Cuatro Cienegas, 3250 ft., July 5, 1952.

The Black-throated Sparrow is common in Coahuila. Typical representatives of _A. b. bilineata_ occur in eastern Coahuila. The center of the State is occupied by intergrades between _A. b.

bilineata_, _opuntia_, and _grisea_. Miller, Friedmann, Griscom, and Moore (1957:381) reported _A. b. bilineata_ from the "Saltillo area."

h.e.l.lmayr (1938:539) recorded _A. b. bilineata_ from Sabinas. The sizes (13, 14 mm.) of the white spot on the lateral tail feathers of Nos.

32163 and 32160, respectively, suggest _A. b. bilineata_. The short wing (61-64.5 mm.) and the lighter and browner color of the backs of Nos. 32163, 32160, and 32161 are suggestive of _A. b. bilineata_.

Nevertheless, the size (8 mm.) of the white spot on the lateral tail feather of No. 32161 indicates intergradation with _A. b. opuntia_.

The sizes of the testes (64 mm.; 8 mm.) of Nos. 32160 and 32161, the size of the largest ovum (2 mm. in diameter) of No. 32163, and the presence of the juveniles from 2 mi. W Jimenez and 5 mi. N and 19 mi. W Cuatro Cienegas indicate breeding by _A. b. bilineata_ in Coahuila.

*_Amphispiza bilineata opuntia_ Burleigh and Lowery.--_Specimens examined:_ total 2: [Female] 31106 from 10 mi. S, 5 mi. E Boquillas, 1500 ft., March 3, 1952; weight, 12.3 gms.; and [Male] 31108 from 35 mi. S, 14 mi. E Boquillas, 2350 ft., March 12, 1952.