APPENDIX. 573 



H. The Outer Covering (InJianenium). 



142. Outer covering (Indmwmtum ; Plilosis). The exterior of the bird in detail. 



143. Feathers (P/«m(p). Composed of ihe stoH and the iceis. 



144. Stem {Scapus). The entire central axis of the fe.ither. 



145. Quill ( Calamus). Tlie hollow horny basal portion of the feather. 



146. Shaft (PJiarhis). The solid terminal portion of tlie stem in which the fibres 



ai'c implanted. 



147. Webs (Pogonia). The series of fibres implanted on each side the shaft, generally 



stitV, and having little 



148. Hooks or barbules along the edges, by which adjacent ones interlock; sometimes 



soft, with the baibules not interlocking, the barbules sometimes wanting. The 



149. Inner web (Pogonium internum) is situated on the inner side of the shaft ; tlie 



150. Outer (externum), on the outer side. 



I51- Vane ( Vesilhun). The shaft and webs taken together, or the portion of the feather 



left when tlie barrel or quill is cut away. 



