1901.] SHUFELDT — OSTEOLOGY OF THE CUCKOOS. 43 



Medius metacarpal well bowed-out from the metacarpal of index 

 digit. Osseous digits long: blade-portion of the proximal phalanx 

 of index digit entire. A notable process at the medio-posterior 

 margin of the medius digit. 



15. Bones of pelvic limb long and slender, and apparently 

 non-pneumatic. Femur slightly bowed forward. A small patella 

 present. Fibula feebly developed. Pro- and ecto-cnemial crests 

 of tibio-tarsus somewhat reduced, and the hypo-tarsus of tarso- 

 metatarsus once perforated for tendons, with lateral grooves for the 

 passage of the same. These grooves are formed by the process 

 being capped with a lamina of bone. Anterior aspect of tarso- 

 metatarsus longitudinally grooved for its proximal moiety. 



Podal digits run 2, 3, 4, 5, for the 1-4 toes respectively, and the 

 fourth toe is permanently reversed. 



Subfamily Centropodin^:. 



Geococcyx californianns. 



1. Superior osseous mandible not especially deep in vertical 

 direction; comparatively broad at base; culmen broadly rounded, 

 very gently curved ; being below the level of the frontal region at 

 the line of the cranio- facial hinge. 



2. External narial apertures situated rather far forward, and 

 small only from the fact that the true nostril is permanently and 

 largely sealed over by an osseous lamina continuous with the side 

 of the mandible. Osseous nostril large in nestling. 



3. Frontal region only moderately broad, and is concaved. 



4. Temporal foss?e well-marked, and well separated behind. 



5. Postfrontal and squamosal processes of nearly equal length. 

 Quadrate, quadrato-jugal bar, pars plana and interorbital septum 

 much as in Crotophaga. Two foramina for nerves over pars plana, 

 only one in Crotophaga. 



6. Form of lacrymal a good deal as we find it in the Anis. 



7. Basipterygoid processes completely absorbed. Pterygoids as 

 in Crotophaga but superior margins not especially sharpened, and 

 with a rudimentary " epipterygoid hook" present. 



8. Vomer always present in adult; small, spiculiform, rod-like 

 and free. Palatines agree mainly with Crotophaga, but their postero- 

 external angles more abruptly rounded off. Maxillo-palatines as in 

 the Anis. 



