Birds of Southern Cameroon. 629 



are equally long and abnndant, the part of the spinal tract 

 behind it is unbroken^ bearing contour-feathers which take 

 their places in the midst of those spriugiug from the 

 saddle. 



(3) Branching End of the Spinal Tract in the Pycnonotidse. 



In most Passerine birds the spinal feather-tract is only 

 gradually and slightly widened at its hinder end, just in 

 front of the oil-gland. In all Pycnonotidse which I have 



Text-fig. 21. 



A B C 



A. Portion of the spinal feather-tvact of Pycnonotus fiaboncnsis. B. Spinal 

 feather-tract of Ploceus higerrimiis. C. Spinal feather-tract of 

 Calatnocichla ru/escens. (See Appeudi.x;, pp. G27, 628.) 



examined, the hinder end of the spinal tract extends laterally 

 into a pair of short branches, one on each side, together 

 forming a short transverse band. The feathers composing 

 these branches are all very short, most of them being merely 

 seraiplumes; but some that stand nearest to the main 

 tract are long enough, in some birds, to reach the light, 

 thus being contour-feathers. 



These lateral branches were very marked in all specimens 

 SEK. IX. VOL. V. 2 u 



