288 BIRDS OF THE REPUBLIC OF PANAMA PART 3 



the edge of tall forest. The National Museum also has a male taken 

 by Goldman near Cana on Cerro Pirre June 6, 1912, and another 

 from Dr. Pedro Galindo from the old Tacarcuna village site on the 

 upper Rio Tacarcuna, July 11, 1963. 



The Goldman specimen had the stomach filled with insect remains, 

 including longicorn beetles, membracids, a caterpillar, and parts of a 

 large moth. Others examined had eaten small berries. 



Webster (Condor, 1963, pp. 383, 399) in a detailed study of these 

 becards has included homochrons and its races as subspecies of 

 Platypsaris aglaiae of Mexico and northern Central America, since 

 males of the two southern forms, hypophaeus of the Caribbean 

 slope and latirostris of the Pacific side, are closely similar in pattern 

 and color. Two males of typical homochrons from eastern Darien, 

 with a faint wash of rose on the throat (collected since Webster's 

 studies), appear to strengthen this resemblance. However, in the 

 series that I have seen, females of the northern forms have a dark 

 crown cap, definitely different from the back, while in the homochrons 

 group of Panama and Colombia the crown is like the rest of the 

 dorsal surface. The two groups obviously are descendants of one 

 stock, but on this difference, clearcut in all specimens seen, appear to 

 have diverged sufficiently to be regarded as two species. 



Ames (Peabody Mus. Nat. Hist., Bull. Z7 , 1971, pp. 40-41, 163) 

 points to "several tyrannid features of the syrinx" in the becards 

 (Pachyramphus, Platypsaris) not found in other Cotingidae. He sug- 

 gests a survey of other features to determine their relationship, with 

 the suggestion that they may be "more closely related to the Tyran- 

 nidae." 



TITYRA SEMIFASCIATA (Spix) : Masked Tityra, Borreguito 



Figure 25 



Pachyrhynchus sciirifasciatus Spix, Av. Spec. Nov., Bras., vol. 2, 1825, p. 31, 

 pi. 44, fig. 1. (Belem, Province of Para, Brazil.) 



Medium size, heavy body ; male, grayish white with black on facial 

 mask, wings and tail ; female, white below, grayish brown above. 



Description. — Length 180-200 mm. Lores and space around eye 

 bare; height of bill equal to width at nostril; nostril separated from 

 frontal feathering ; gonys about as long as mandibular rami. Adult 

 male, ninth primary slender, shortened, about half as long as eighth 

 and tenth ; forecrown back to middle of eye, side of head and chin 

 black; rest of head white to grayish white; back, scapulars, lesser 



