1866.] MR. SCLATER ON THE AMERICAN CAPRIMULGID^E. 127 



cut in beyond the inner pair as in Podargus. Unfortunately I am 

 not able to show a sternum of the curious form Steatornis ; but M. 

 Blanchard has given a figure of it (Oste'ologie, pi. 3. f. 3), whereby 

 it appears that it resembles that of the typical Caprimulyince in the 

 outline of the posterior margin, but has the general squared confor- 

 mation of that of the Podaryince. Under these circumstances I think 

 we may divide the Caprimidyidce very naturally into three different 

 subfamilies as follows : — 



Subfam. I. Podarginje. 



New World. 



4. Nyctibius. 



Claw of middle toe not pectinated; 



outer toe with five phalanges ; sternum 



with two pairs of posterior fissures. 



a. Outer pair of posterior fissures 



much deeper than inner pair ; 



tarsus long and naked ; eggs 



colourless 



h. Outer pair of posterior fissures 

 not deeper than inner pair ; 

 tarsus extremely short, and 

 feathered ; eggs coloured . . 



Subfam. II. Steatornitiiin^e. 



Claw of middle toe not pectinated ; 

 outer toe with five phalanges ; sternum 

 with one pair of shallow posterior 

 fissures ; eggs colourless* 1. Steatornis. 



Subfam. III. Caprimulgin^e. 



Claw of middle toe pectinated ; outer toe 

 with four phalanges only ; sternum 

 with one pair of shallow posterior 

 fissures ; eggs coloured. 



Old World. 



1. Podargus. 



2. Batrachostomus. 



3. Mgotheles. 



a. Glabrirostres : rictus smooth . 



' 1. Podager. 



2. Lurocalis. 



3. Chordeiks. 



y- 



b. Setirostres : rictus armed with 

 strong bristles 



4. Lyncornis. 



5. Eur ystopodus^ 



6. CaprJmulgus\ 



7. Scotornis. 



8. Macrodipteryx. 



9. Antrostomus. 



10. Stenopsis. 



11. Hydropisalis. 



12. Heleothreptus. 



13. Nyctidromus. 



14. Siphonorhis. 



I now proceed to discuss the American species of these three sub- 

 fftmilics * 



Subfam. 1. PODARGIN^. 



Of this subfamily there is but one genus in the New World, 

 namely 



Nyctibius, Vieill. 



Besides the very short and feathered tarsi, this genus is distinguish- 

 * Cf. Des Murs, Rev. Zool. 1843, p. 33 ; et Trait. d'Ool. Orn. p. 259 et seq. 



