Pachyramphus major itzensis Nelson: Mexican Becard.—Previous records of breeding in this species are provided by a female obtained on July 12 (Paynter, 1955a:182) and a male taken on June 9 (Paynter, 1955b).
Specimen (1): ♂, 40625, testis 9 × 5 mm., 22.1 gm. (July 21), Pisté.
Platypsaris aglaiae (Lafresnaye): Rose-throated Becard.—All specimens have extensively worn plumage.
Specimens (3): ♂, 40628, 33.5 gm. (July 10), 5 km. S Champotón; ♀, 40626, ovary 6 × 3 mm., brood patch, 34.0 gm. (July 20), ♀, 40627, ovary inactive, 33.9 gm. (July 26); 3½ km. N and 6½ km. W Pisté.
Tityra semifasciata personata Jardine and Selby: Masked Tityra.—Previously, breeding information for this species has been available only for March (Paynter, 1955a:184). Adults were observed feeding young fledglings 7½ km. W Escárcega on July 15, and a juvenile was taken. Gonads of males were in full breeding condition.
Specimens (5): ♂, 40630, testis 13 × 6 mm., 81.3 gm. (July 14), sex? 40631, juv., 55.5 gm. (July 15), ♂, 40632, testis 9 × 5 mm., 73 gm., molting—1st and 2nd primaries ensheathed (July 15), and ♀, 40633, 84.7 gm. (July 16), 7½ km. W Escárcega; ♀, 40629, ova to 1 mm., 80.0 gm. (July 23), Pisté.
Erator inquisitor fraserii (Kaup): Black-capped Tityra.—Breeding has been recorded by Paynter (1955a:185) on April 26. A moderately enlarged testis (probably regressing) was noted in the specimen from Pisté, on July 21.
Specimens (2): ♀, 40635, 51.8 gm. (July 15), 7½ km. W Escárcega; ♂, 40634, testis 6 mm., 51 gm., molting—6th primaries ensheathed (July 21), Pisté.
Pipra mentalis mentalis Sclater: Red-capped Manakin.—The specimens here reported seem to be the first from the peninsula in which reproductive activity has been recorded.
Specimens (2): ♂, 40637, testis 5 × 3 mm., 14.0 gm. (July 29), Pueblo Nuevo X-can; ♂, 40636, testis 5 × 2 mm., 14.6 gm. (August 3), 4 km. WSW Puerto Juarez.