596 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



becomes a strong single band, which forks behind so as to more or 

 less surround the oil gland. The humeral tracts are strong and 

 usually broad and the parapterum is very evident. There are two 

 complete rows of primary coverts, and on the forearm there are seven 

 or eight rows of feathers, of which the lower three or four are true 

 secondary coverts. The femoral tract is very strong and evident, 

 running obliquely across the upper end of the tibia from the knee, 

 along on the posterior edge of the femur. The tibia and tarsus are 

 usually veiy completely covered with feathers, and often the toes 

 also. At the base of the gonys the infra-mandibular region is very 

 thickly feathered, but this dense patch divides abruptly and either 

 passes up on each side and runs along the ear-conch, as in those owls 

 in which this conch is fully developed, or, as in other species, disap- 

 pears on the rami of the lower Jaw. The rest of the chin and throat 

 are veiy sparsely feathered in most owls, but in others it is fully cov- 

 ered. The lower cervical tract is narrow and is divided on the neck 

 so as to pass down on either side to form the strong sternals. It is 

 also connected with the humerals, and especially with the triple row 

 of small feathers on the lower edge of the patagium, while aU of the 

 upper outer corner of the breast is usually more or less feathered. 

 From the lower end of the sternal tract there runs a strong hook over 

 to the hypopterum, which is itself very evident. There are two rows 

 of primary and three or four of secondary under coverts. The ventral 

 tracts commence on the breast, usually near the furcula, and seem 

 to be fused with the sternals at first, but soon separate from them and 

 run down on either side almost to the anus, becoming very narrow 

 on the beUy. Strix [i. e. Tyto] shows a very peculiar modification of 

 this typical form, in the fusion again of the sternal and ventral tracts 

 at the posterior end of the former. The post-anal tract, comprising 

 the under-tail coverts, is strong and very conspicuous in the larger 

 species. All of the specimens of Striges examined agreed in the 

 following details: 



"Aftershafts wanting. True down wanting. Oil gland not tufted. 

 Primaries 11, the eleventh very small. Kectrices 12 (except Micro- 

 paUas). Alula feathers 4. Wing aquincubital." 



It is now definitely settled and pretty generally admitted that the 

 owls are much less intimately related to the true Birds of Prey 

 (Accipitres) than to the Coraciif ormes, among which their nearest rela- 

 tives, apparently, are the Nycticoracise, especially the suborder 

 Steatomithes (represented only by the Guacharo or Oil Bird, Stea- 

 tomis caripensis) , though, in reality, the gap between these and the 

 Striges is a very considerable one. Nevertheless, the resemblance : 

 to the Accipitres is mainly one of adaptation, both groups being emi- 

 nently "raptorial" in their nature, and therefore provided with a 

 strongly hooked bill and relatively long, strongly curved, and sharp 



