I'ext-fio'ui'e 5. 



cr.pro. 



Diagram indicating the structure and relationships of the mesoptile with the pro- 

 toptile and with the true feather in the Chinese Goose. The mesoptile shaft 

 (sh.jnes.), which lies between the protoptile shaft (sh.pro.) and the tip of a true 

 feather, consists of numerous barbs and of a band representing a rhachis. Con- 

 tinuous with the rhachis is a perforated band from which slender cords (c.) 

 proceed to the barbs forming the tip of the true feather (tel.). The mesoptile 

 afterehaft is also continuous with a perforated band which ends in a vestige of 

 an aftershaft of the true feather (af.t.). From the perforated hand slender 

 cords (c 1) proceed to barbs near the tip of the true feather. It will be ob- 

 served that the aftershaft of the protoptile consists of twelve well-developed 

 hurbs armed with numerous bavbnles. 



