136 



Genus HERPETOTHERES, Vieillot. 



" ? Fhyseta Vieillot, 1816 (suppressed in 1818)." [Fide G. R. Gray.] 



Herpetoiheres Vieill. Nouv. Diet. d'Hist. Nat. xviii, 1817, 317 (type Faleo tachinimns 



Linn.). 

 Cacldnna Flem. Phil. Zool. ii, 1822, 236 (same type). 

 Maeagua Less. Traite d'Orn. 1831^ 68 (same type). 



Osteology. — Scapular process of the coracoid produced forward so as to 

 meet the clavicle. Nasal bones almost completely ossified, leaving- only 

 a small circular nasal orifice with a firm bony rim and inclosed bony 

 tubercle, inferior surface of the supramaxillary with a median angular 

 ridge. Superciliary process of the lachrymal greatly developed, consist- 

 ingof a single broad piece extending nearly across the orbit. Posterior 

 margin of the sternum truncated, entire, without foramina. General ap- 

 pearance and size of the skull exceedingly like that of Falco communis^ 

 but the supero-frontal width much greater, and the palatine surface cor- 

 respondingly narrower ; iuterorbital width of the frontal bone more than 

 half the length of the skull from the base of the maxillarj^; width of 

 the superciliary processes more than one-third their length ; width of 

 the conjoined palatines less than twice the width of the superciliary 

 process, and less thau half their own length ; tomium of the supramax- 

 illary without tooth or notch; nostril o]iening against the anterior edge 

 of the cere, its bony rim much elevated on the posterior side. Mandible 

 very broad and strong, with a large, longitudinal, oblong-ovate vacuity. 

 Keel of the sternum about equal in length to the scapula, much longer 

 than the coracoids and furcula; greatest width of the sternum about 

 two-thirds its length.* 



General external features. — Bill much compressed, xQvy short and deep, 

 its height through the base being about equal to the chord of the culmen^ 

 whose cnrve forms about one-third the circumference of a circle ; gonys 

 very convex, ascending abruptly terminally; superior tomium very 

 slightly sinuated ; end of the lower mandible divided frontally by an 

 angular notch. Cere short, almost concealed by the rigid bristles of the 

 lores and forehead. Xostril large, circular, against the anterior edge of 

 the cere, its bony rim much, elevated superiorly and ijosteriorly, and its 

 bony tubercle not prominently exposed. Feet very robust ; tarsus 

 longer than the middle toe ; lateral toes nearly equal, but the outer ap- 

 preciably the longer; membrane between middle and outer toes well 

 developed. Covering of tarsus and toes consisting of irregularly hex- 

 agonal, roughly imbricated, small scales, with no tendency to larger 

 size on any part ; terminal joint of the toes with three broad scutellae.. 

 Claws normal, of moderate length and curve, the edges unusually sharp. 

 Fterylosis. — Distribution of the tracts much as in Falco, but with the 

 dorsal stem of the spinal tract enlarged on all sides, undivided, and 

 sparsely feathered. Lumbar tracts distinct, but short and separated 

 from the crural tracts. Inferior tract narrow in all its parts, inner 

 branch indistinct at the end of the gular portion ; outer branch com- 

 pletely separated from the pectoral stem, somewhat broader than the 

 parrow main stem itself, and distinct from it; ventral portion of the 

 main stem removed far outward, running along the margin, and 

 terminating laterally in front of the anus. — (Nitzsch.) 



Plumage full and soft, except about the head ; feathers of the crown 

 developed into a full depressed crest of lanceolate feathers with very 

 rigid shafts ; orbital region with scattered hairs ; ejelids strongly 



* There are no other bones of this remarliable form accessible for examination. 



