1894. PBOCEEDINGS OF THE NATIOXAL MUSEUM. 553 



lower cervical tract forks at about tlie middle of the neck and each 

 branch extends down over the side of the breast, where it is very broad 

 and strong, and then (as it enters on the surface of the abdomen, or a 

 little before) suddenly contracts to a strip only two rows broad, whicli 

 curves inward and ends a little in front of the anus. The hypopterum 

 is generally very evident and connects the sternal tract with the iucom- 

 ])lete fourth row of under wing coverts. The lower surface of the wing 

 is very slightly feathered, but there are two complete rows of primary 

 and three of secondary coverts and iiu incomplete fourth row of the 

 latter. The four genera agree also in the following details: 



Aftershafts ijresent but weak. True down wanting. Oil gland not 

 tufted. Primaries, 10. Eectrices, 10. Alula feathers, 3. Seconda- 

 ries, 12 or 13, but the wing is aquincubital. 



The larger wing and tail feathers are all peculiar in the length of the 

 <juill {calamus) and the corresponding shortening of the shaft (rhacis) 

 which ends with the vexilhi^ The four genera fall naturally into two 

 groups, as follows: 



I. Secondarioa, 12; tail not forked, tlio central pair of rectrices loriifest ; rictal l>ris- 



tles very prominent; iufra-mandibnlar region sparsely feathered; no iuuer 

 branch or tooth on the lower cervical tract. 



A. Only 8 complete longitndinal rows of feathers on the crown. Tarsns not 



feathered at all PHAi>.i:xt)PTii,.u.s. 



B. Eight complete rows, but tarsns feathered halfway down in front. 



Antrostomus. 

 (!. Ten complete rows and tarsns not feathered Nyctidromus. 



II. Secondaries, 13; tail forked, central pair of rectrices shortest; rictal bristles not 



evident; inframandibnlar i-egioa well feathered; lower cervical tract with 

 a prominent inner tooth. 

 A. Ten complete rows on crown. Tarsus feathered in front Chordeile.s. 



Genus P H AL .E N O.PT I L U S . 



Of this genus I have only had .the opportunity'to examine one speci- 

 men, but as that was in good condition, it probably illustrates correctly 

 the pterylosis of the genus. As the primaries had been cut off, the 

 formula for' their comparative lengths cannot be given, but there were 

 12 secondaries. On each side of the head, along the edge of the rictus, 

 there is a single row of long, stout, bristle-like feathers. Above this 

 is a second row of smaller contour feathers and above this a third 

 incomplete row of the same. From the base of the culmen (fig. 1) 

 there run backward on each side two rows of contour feathers, so near 

 together as to almost make a single row. For a short distance these 

 double rows are about parallel, and then curving inward they unite 

 for a short distance into a band three rows broad. On the crown they 

 separate once more into four distinct roAvs, which, although somewhat 

 curved, are almost parallel* for some distance, but unite again at 

 the commencement of the cervical tract. Another row begins on each 



* Used in the sense of being equidistant at all points. 



