THE PIGEON {Columha livia, var. domestica) 



First Day 

 External Features. 



1. Make a drawing of the Pigeon, viewed from the side, showing : 



(a) The mouth, with the elongated upper and lower portions of the horny 



beak. 



(b) The cere, a swollen area of soft skin at the base of the upper beak. 



(c) The nostrils (external nares), between the upper part of the beak and 



the cere. 



{d) The large eyes, each with an upper and a lower eyelid and a semi- 

 transparent nictitating membrane or third eyehd (at the inner angle 

 of the eye). 



(e) The external auditory apertures, situated a short distance behind the 

 eyes and concealed by the feathers. 



if) The fore- limbs, which are modified as wings, being provided with long 

 flight-feathers and expansible membranes about the arm-pit. 



ig) The hind-limbs or legs, the proximal part of each being covered by 

 small feathers, while the distal portion and the foot has a covering of 

 scales. The first of the four clawed toes is directed backwards. 



(h) The various sets of feathers, viz. : — 



(i) The remiges or wing feathers. Those attached to the bones 



of the hand or manus are the (eleven) primaries, and those 



attached to the ulna are the secondaries, 

 (ii) The ala spuria or bastard wing, a small tuft of feathers on the 



anterior border of the wing, attached to the phalanx of the 



first digit (thumb), 

 (iii) The rectrices or tail feathers. 



(iv) The contour feathers covering the general surface of the body. 

 (v) The wing and tail coverts covering the bases of the quills. 



2. Remove a wing-feather and make a drawing of it to show these parts : 



(a) The calamus or quill, the transparent hollow proximal part of the 



longitudinal axis or stem of the feather, with the inferior umbilicus 

 at its base and the superior umbilicus just below the vane. 



(b) The rachis or shaft, the distal solid part of the axis, bearing the vane. 



(c) The vane or vexillum, attached on either side of the rachis and made up 



of barbs interlocked by barbules. 



(d) The aftershaft or hyporachis, a small tuft of down situated in the 



neighbourhood of the superior umbilicus. 



The Mouth Cavity. 



Open the mouth widely and make a sketch showing the following parts : — 

 (a) The tongue, triangular and sharp-pointed. 



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