126 Proceedings of the Biological Society of Washington. 



Middle America, Part IV, p. 101, and Phillips, A Year's Collecting in 

 the State of Tamaulipas, Mexico, The Auk, Vol. XXVIII, p. 80. 



Remarks. — All specimens from Central and Northwestern Mexico should, 

 I think, be referred to T. migratorius propinquus, those from northern 

 Tamaulipas are more or less intermediate, while all from southern 

 Tamaulipas and the mountains of Vera Cruz belong to the new form. 



I use the generic name Titrdus, not because I consider the American 

 Robin more nearly related to the spotted thrushes than to the members 

 of the so-called genus Planesticus, but because I agree with most European 

 ornithologists in failing utterly to understand why such intimately related 

 forms should be separated generically. 



Cyanocompsa parellina beneplacita subsp. nov. 



Type from Santa Leonor, Tamaulipas, Mexico. Adult c?. No. 49,685, 

 Coll. Mus. Comp. Zool. Collected April 5, 1909, by F. B. Armstrong. 



Characters. — At once distinguished from all the other subspecies by 

 having a much shorter, narrower, more fringilline bill, which in the c? is 

 wholly black, in the 9 dusky horn color; the mandible scarcely paler. 



Adult (^ duller and grayer blue than the adult d of C. parellina 

 parellina (Bp. ) of Vera Cruz to Yucatan, some examples nearly as pale 

 as C. parellina indigoiica Ridg. of western Mexico (as a whole the series 

 is about intermediate in color between these two forms). Adult $ , much 

 paler and grayer brown, both above and below than the $ of C. p. 

 parellina, not very different in color from the Q of C. p. indigotica. 

 Size, except bill, about as in C. p. parellina, smaller than in C. p. 

 indigotica. 



Measurements.— Type, adult d". Wing, 68; tail, 55; tarsus, 19.5; 

 culmen from base, 10.5; width of mandible at base, 7. Adult 9 topotype 

 No. 49,682, wing, 66; tail, 52; tarsus, 18.5; culmen from base, 10; width 

 of mandible at base, 6.5. Extreme measurements afforded by ten other 

 males are— wing, 67-70.5; tail, 52.5-57; tarsus, 17-19.5; culmen from 

 base, 10-11; width of mandible at base, 6.5-7.5; by three other females 

 —wing, 64-65 ; tail, 50-52; tarsus, 18-19; culmen from base, 10-10.5; 

 width of mandible at base, 6.5-7. 



Remarks.— Whi\e collecting for Doctor Phillips in Tamaulipas, F. B. 

 Armstrong secured twenty-six specimens of this well-marked form. All 

 from the hill country in the west central part of the state are typical. 

 Several skins, however, from Altamira in the southeastern corner of 

 Tamaulipas are decidedly intermediate in all characters, and might 

 almost as well be referred to C. p. parellina as to the new form. 



It is possible a still further subdivision should be made and the Yucatan 

 form be given a name. It is similar to the Vera Cruz bird in size and in 

 size, shape and color of the bill, but three out of our four adult males are 

 very bright blue below, much more brilliant than in any Vera Cruz skin ; 

 the fourth specimen, however, is not different from A'era Cruz examples. 



