1881.] MR. W. A. FORBES ON THE GENUS CONOPOPHAGA. 437 



ill Calyptomena, and va. Hadrostomus, Tityra (just), and Lipaugus, 

 but in none other of the Pipro-Cotingidae. The only Tyrannine bird 

 in which I have observed it is Arundinicola leucocephala. 



From the character of its skull nothing very definite can be 

 predicated of Conopophaga, except that it clearly has no relation to 

 Furnariine forms. In its visceral anatomy, myology, pterylosis, and 

 other characters I have detected no deviation from the ordinary 

 Passerine structure. The typical arrangement of the tensor patagii 

 brevis tendon is somewhat concealed, as in Pteroptoehus and Hy- 

 lactes (cf. Garrod, P. Z. S. 1876, p. .510), by the muscular fibres 

 at the origin of the extensor metacarpi muscle. There is no trace 

 of a vinculum in the deep flexor tendons of the foot. The artery of 

 the leg is the sciatic. In the tarsi the anterior scutes, about six in 

 number, extend round to the posterior margin exteriorly, leaving 

 the internal plantar space covered by a smooth skin, with no signs 

 of scutes or scutellse. In its possession of an " exaspidean " ' tarsus, 

 Conopophaga differs from all other forms of Tracheophonse, and 

 resembles Oxyrhynclius, the Tyrannidse, and Pipridse alone of Pas- 

 serine birds. 



The Tracheoplwne syrinx of Conopophaga aurita has been briefly 

 described and figured by Miiller" ; and from that species C. Hneata 

 does not essentially differ. I find, however, that in this latter species 

 the commencement of the tracheal syrinx is less abrupt than is 

 depicted by Miiller, the few preceding tracheal rings, particularly 

 posteriorly, becoming gradually less and less deep as they approach 

 the membranous part. The last tracheal ring is deeper and stronger 

 than its predecessors, and is incomplete in the middle line behind. 

 The first bronchial semiring is considerably stronger than the second 

 one, and bears the processus vocalis, which extends upwards for 

 about two rings. The last tracheal and first two bronchial semirings 

 are less closely connected together than in Miiller's figure. The 

 tracheal syrinx forms a somewhat dilated tympanum. As regards 

 the muscles, my observations agree with Miiller's as to there being 

 no intrinsic muscles, as the lateral tracheal muscle stops at the com- 

 mencement of the membranous part of the trachea, from which 

 place also the sterno-tracheales diverge. 



This syrinx of Conopophaga does not exactly agree with that of 

 any other Tracheophone group. In that it possesses processus 

 vocales it resembles that of the Furnariidse and Dendrocolaptidse 

 described by Miiller {Pteroptoehus, Hylactes, Formicarius, and 

 Grallaria), and differs from Thamnophilus and Hypocnemis. In 

 the absence of any intrinsic muscle it resembles Grallaria and Hy- 

 lactes, as described by Garrod, as well as Chamceza, Pteroptoehus, 

 and Formicarius. In Furnarius, Dendrocolaptes, &c. this muscle is 

 always present, and double. But in both Grallaria, Hylactes, and 

 the others the sterno-tracheales muscles arise from the end of the 

 vocal process. In Conopophaga, on the other hand, they leave the 

 trachea before reaching that process. 



' As defined by Sundevall, I. c. p. 57. 



2 L. c. p. 39, pi. vi. fig. 12. Garrod's ed. p. 32. 



