Specimens from the barrier island are clearly referable to C. m. prosopidicola, showing no approach to the larger and, in the female, darker C. m. mexicanus of Veracruz and San Luis Potosí. In Table 4, measurements of the adult male from the barrier island may be compared with those of specimens of C. m. prosopidicola from Texas and a specimen of C. m. mexicanus from Veracruz; it is apparent that our specimen is assignable to the former.
Evidence of intergradation between the two subspecies is shown in a series of birds collected near Ciudad Victoria, Tamaulipas, in May, 1961. The females in the series are highly variable in color individually, but are on the average paler than C. m. mexicanus from Veracruz; the males are distinctly larger than C. m. prosopidicola from Texas. At Miramar, near Tampico, Tamaulipas, a decided approach to C. m. mexicanus is also evident in the dark color of females and in the large size of both males (Table 4) and females.
Agelaius phoeniceus megapotamus Oberholser: Red-winged Blackbird.—This species was recorded only at Camp 1 on July 7, when we saw two males, one of which was flying south along the edge of the dunes in a flock of five Great-tailed Grackles. Specimen: ♂, 38992, testis 10 × 7 mm., fat, 54 gm., Camp 1, July 7. The large size of the testes of this individual indicates breeding condition.
Sturnella magna hoopesi Stone: Eastern Meadowlark.—Meadowlarks were found in small numbers along the margins of the alkaline flats at both camps. Breeding was still in progress, for males were singing and a female shot on July 9 had only recently laid eggs. Specimens (2): ♂, 38986, testis 13 × 8 mm., not fat, 102 gm.; ♀, 38987, ova to 6 mm., 3 collapsed follicles, not fat, 88 gm.; Camp 2, July 9.
Richmondena cardinalis canicaudus Chapman: Cardinal.—This species was recorded only in stands of mesquite near Camp 1, as follows: July 7, two pairs seen, from which a breeding female was taken; July 8, three birds seen. Specimen: ♀, 38933, edematous brood patch, 36.5 gm., Camp 1, July 7. Intergrades between the present subspecies and R. c. coccinea of Veracruz are reported from Altamira, Tamaulipas (Mexican Check-list, 1957:329).
Mammals
Dasypus novemcinctus mexicanus Peters: Nine-banded Armadillo.—Remains of an armadillo (89017) were found in a mesquite thicket in the dunes near Camp 1 on July 7. The bones are not badly weathered and were not embedded in sand.
This species has not been recorded previously on the barrier island of Tamaulipas, nor, for that matter, on any of the barrier islands on the western shore of the Gulf of Mexico.
Lepus californicus merriami Mearns: Black-tailed Jackrabbit.—From two to four individuals were recorded daily in dunes and on alkaline flats in the vicinity of stands of mesquite and cactus.
Specimens (2): ♀ adult, 89018, pregnant (two embryos, 28 mm. in crown-rump length), Camp 1, July 6. Male immature, 89019, Camp 1, July 7. Our specimens have been compared with two skins of L. c. curti from the type locality at Eighth Pass, with which they agree reasonably well in color. The size of the adult female is about that characteristic of other specimens of adult L. c. curti, but characters of the skull are consistent with those of L. c. merriami.