488 PASSERIFORMES : FORMICARIIDAE CHAP. 



Fam. X. Formicariidae. The so-called "Ant-birds" not 

 known to live on ants are plentiful in the forests of northern South 

 America, whence the numbers decrease to Central America, Chili 

 and Argentina. Of the two hundred or more species none inhabit 

 the Antilles, but three occur in Trinidad and one in Tobago. Mr. 

 Sclater l allows as provisional Sub-families the strong Thamnophil- 

 inae, the weaker Formicariinae, and the long-legged Grallariinae. 



The beak is strong, compressed, hooked, and terminally toothed 

 in the Thamnophilinae, being exaggerated in Batara, large and 

 swollen in Cymbilaniu&,8aid exceptionally hooked in the former genus 

 and Pygoptila ; CymMlanius, Neoctantes, and Clytoctantes have 

 the genys upturned. In the Formicariinae the bill is weaker 

 and but slightly hooked, being very long and thin in Rhamplio- 

 caenus ; in the Grallariinae it is usually elevated and compressed, 

 though broad in Pittasoma. The taxaspidean metatarsus (p. 471) 

 is moderate or short in the Thamnophilinae, and remarkably long 

 in the G-rallariinae, where it may be very strong, as in Pittasoma ; 

 among the Formicariinae it is short and thick in Ehopoterpe and 

 Formicivora, long and thin in Psilorliamplius and Formicarius, 

 and so forth. In Phlogopsis, Psilorhamphus, MJiampliocaenus, 

 Jfeterocnemis, Myrmeciza, Hypocnemis, Pithys, and Gymnopitliys 

 the scutes are nearly fused. The outer and middle toes are joined 

 towards the base. The wings, which have ten primaries and 

 nine secondaries, are normally short and rounded, though longer 

 in Rhopoterpe ; the tail is commonly long and broad in the 

 Thamnophilinae, varies greatly in the Formicariinae, and is very 

 short and square in the Grallariinae. It may be rounded or 

 graduated in the first two Sub-families, and Terenura has it 

 remarkably thin ; Cercomacra, Formicivora caudata, and F. ferru- 

 ginea have only ten rectrices in place of the usual twelve. 

 Thamnomanes has well-developed rictal bristles, RhampJiocaenus 

 has the nostrils in a groove and partly covered by a membrane. 



The sexes are similar, and mainly reddish-brown, in RJiampTio- 

 caenus, Phlogopsis, and the Grallariinae ; but generally the males 

 are black and white, black, grey and brown, or uniform black ; 

 and the females ferruginous, more or less relieved by black and 

 white. Cross-bars, spots, and striations are not uncommon, 

 the white often shewing as a band on the tail, an edging to the 

 wing-coverts, or exceptionally, as in Pygoptila margaritata, as 

 1 Cat. Birds Brit. Mus. xv. 1890, p. 177. 



