NO. 2251. THE ANATOMY OF NYCTIBIUS—WETMORE. 579 



the anterior end the two lobes were connected by a band of liver 

 tissue 7 mm. long. This band was broad where it joined the left 

 lobe, expanded by a rounded process on its lower margin, and then 

 contracted to a narrow neck to join the right lobe. The small size 

 of the left liver lobe is unusual, as in allied forms concerning which 

 information or specimens are available (Podargus, Caprimulgus, 

 Phalaenoptilus, Setochalcis, Nyctidromus, and Chordeiles) the left 

 lobe is much larger, being from one-third to more than one-half the 

 bulk of the right hand division. 



A small elongate gall bladder similar to that found in other Capri- 

 mulgi (including Chordeiles'^) underlaid the right lobe of the liver in 

 a notch near the external margin. The pancreas was small, consisting 

 of a single lobe that was rounded and full at the lower end, elongate 

 and attenuate above. It was not possible to trace the hepatic and 

 pancreatic ducts in this specimen to the point where they entered the 

 intestine. 



The spleen was placed against the anterior end of the gizzard on 

 the right side, beneath the upper end of the right liver lobe. It was 

 elongate with bluntly rounded ends, flattened somewhat from side 

 to side, but in general form was cylindrical. The spleen measured 

 10 mm. long and the flattened face was 2.5 mm. broad. 



There was only one carotid artery, a character in which Nyctibius 

 resembles Podargus and differs from the Caprimulgidae. The left 

 carotid passes up out of the body cavity, and then swings over to 

 run on up the neck through the hypapophysial canal, as in a 

 specimen of Podargus strigoides (Cat. No. 19361, U.S.N.M.) ex- 

 amined. In Nyctibius there is a small artery on the right side that 

 extends to the right thyroid gland. A branch of this artery then 

 proceeds inwards as a vertebral artery but extends no farther up 

 the neck. 



In the specimen of Nyctihius at hand the trachea was injured so 

 that a detailed study of it was not practicable. It was ascertained, 

 however that the syrinx was tracheo-bronchial, in which character 

 this genus resembles the Caprimulgidae. 



The sternum has been studied so no details of the trunk skeleton 

 need be given save to note that the procoracoidal process is small, 

 not reaching the clavicle, and that there are 14 cervical vertebrae of 

 which three bear free ribs. 



There is some confusion in published accounts as to the number 

 of cervical vertebrae in this group. Beddard ^ states that Chordeiles 

 possesses 13. Gadow^ gives 14 for Podargus and Batrachostomus 

 and 13 for Caprimulgus. Fiirbringer * says that Caprimulgus has 13 



1 Wetmore, Proc. Biol. Soc. Washington, vol. 28, 1915, pp. 175-176. 



2 Structure and Olassiflcatlon of Birds. 1808, p. 241. See also Oberholser, A mono- 

 graph of the Genus Chordeiles, U. S. Nat. Mus. Bull. 80, 1914, p. 9. 



« Bronn's Klassen and Ordnungen des Thier-Reichs, Vogel, vol. 1, 1891, p. 950. 

 * Untorsuchungen zur Morphologic and Systematik der Vogel, vol. 1, 1888, table 23. 

 pp. 780-781. 



