1885.] TROCHILTD^, CAPRIMULGID^, AND CYPSELID^. 913 



Vomer has its rather pointed anterior end resting between inaxillo- 

 palatines in this genus ; broadly rounded and free in Phalcenoptilus ; 

 truncated in CaprimuUjus (Huxley). Palatines broad, and with 

 rounded postero-external angles, anchyiosed together at their heads 

 (separated in P. nuttalli). Basipterygoid processes present. Man- 

 dible has the ramal portions in slender pieces from the slender den- 

 tary part. Basibrauchials of hyoidean apparatus co-ossify in this 

 genus, but are in two pieces in P. nuttalli. 



2. Sternum broadly 1-notched ; carina deep; no manubrium. 



3. Bones of pectoral limb harmoniously proportioned, and present 

 no special peculiarities. The radius and ulna are considerably 

 longer than humerus. Patella absent in pelvic limb. Hypotarsus 

 of metatarsus impierced for tendons. Formula for podal digits 

 2, 3, 4, 4. 



0/ Panyptila saxatilis : — Characters of, 1, the skull essen- 

 tially agreeing with those given by Huxley for Cypselus apus, and 

 presented in detail above. 



2. The spinal column contains 35 vertebrae and a pygostyle. 

 Xiphioidal border of sternum entire and rounded ; carina moderately 

 deep only. A manubrium of no small size is developed. Coracoids 

 and scapulae in the slioulder-yirdle something like the Swallows, but 

 furcnlum has the abutments on the outer sides of the clavicular heads 

 for the coracoids. 



3. Shaft of humerus short, radial crest curled towards the humeral 

 head. Non-pneumatic. Ulna and radius both straiglit, the former 

 considerably longer than the humerus. (Sesamoids absent in the 

 arm ?) Carpo-metacarpus large and longer than the antibrachium. 

 Digits normal and differing in form entirely from Trochilus. 



Skeleton of pelvic limb characteristic. Lower end of tibio- tarsus 

 peculiarly twisted. Pro- and ectocnemial ridges not developed 

 (negative character). No patella. Fibula does not extend below 

 the articular ridge of the other leg- bone (this is also the case in 

 some Parrots, Conurus). Hypotarsus of tarso-metatarsus containing 

 one deep groove. Formula for digits of pes, 2, 3, 3, 3, as in all 

 the Cypselidae. 



Conclusions. 



Huxley's investigations of this gronp in 1867, led him to believe 

 that " the Caprimulgidse come near Trogon, and more remotely 

 approach Podaryus and the Owls." Six years afterwards Garrod 

 threw not a little light upon this question by his careful dissections 

 of Steatornis, although this talented anatomist still left that bird's 

 position in the system a matter of doubt. 



My own studies of the skeletons of these forms, including Surnia 

 funerea and many other Owls, strongly incline me to the opinion 

 that one group should be made to contain all the typical Caprimul- 

 ginc forms, as well as Nyctibius, Steatornis, and, no doubt, others, 

 as Podargus and Psalurus, the skeletons of which I have not yet 

 examined. 



Such a group, or an order, might be well termed the Caprimulgi ; 



