166 



ORTHOGENETIC EVOLUTION IN PIGEONS. 



removed on account of his insistence upon sole possession of the ledge of their ample 

 breeding-pen. None of these birds had really shown any inclination to mate, and 

 the sex of none of the three was known. Beginning in the winter of 1911-12, a 

 more determined attempt was made to mate M N 1 . Three or four Columba guinea 

 which I later found included both sexes and included also the mutant father- 

 were offered, one after the other, without the slightest success. The "tameness" 

 of this bird remained undiminished, until it died of tuberculosis at just 2 years of 

 age; it was then found to be a female. This record would seem to indicate that the 

 bird was a weak individual. The later plumages, when 1 and 2 years old, were 

 certainly as strikingly different from the normal as when 4 weeks old. It was often 

 noted that it had less of the lighter gray of its mutant father, but was much farther 

 removed in the direction of its sire from the normal guinea type, the red being 

 greatly diminished and the guinea-mark dark grayish, with much less distinct 

 boundaries, the effect always suggesting the black-chequered wing of the chequered 

 rock-pigeon. The bird always bore its feathers somewhat loosely, as if it had just 

 shaken them and then failed to pull them into place. 



The breeding of the original mutant (20) was wholly neglected during 1911. 

 Much of the season of 1912 was lost in the attempt to effect a mating with his mutant 



TABLE 5. Breeding record of mutant Columba guinea, No. SO. 

 <? C. guinea (20), May 7, 1909 to Nov. 7, 1914; mutant; brother. 

 9 C. guinea (10), Oct. 18, 1908; normal (or nearly ") ; sister. 



Al. May 5, 1910; no development. 



A2. May 7, 1910; no development. 



Bl. May 28; no development. 



B2. May 30; no development. 



Cl. Sept. 23; MN1 ; 9 MUTANT, like sire; dead Oct. 8, 1912 



C2. Sept. 25; MN2; MUTANT (?); dead at 14 days. 



9 C. guinea " (had lost tag) ; normal ; probably a sister 



to mate (No. 20). 

 Al. Apr. 6, 1914; broken. 

 A2. Apr. 8, 1914; broken. 

 B. Apr. 20; broken; no second. 



| Cl. May 9; no development (care?). 



C2. May 11; broken. 



Dl. June 16; broken. 



D2. June 18; no development. 



El. Aug. 7; hatched; dead at 3 days; <? (?). 



E2. Aug x 9; hatched with help; upper beak too short; died 



at once; c? (?). 

 Fl, Gl, HI, II, Jl\ 

 F2, G2, H2, 12, J2J 

 Kl. Nov. 5; no development. 

 K2. Nov. 7; live 7-day embryo." 



used in other studies (analyses of yolk). 



The sire (<? No. 20) died of fright (?) and hemorrhage from liver, Nov. 17, 1914. 



' The third right primary has two spots near the tip one on each side; this is a case of abnormal albinism. 



17 This female was mated to the "mutant" (No. 20) in 1914; the record is that obtained by the editor. 



18 Yolk-sac so little advanced that egg was opened by mistake; possibly would have hatched. 



EXPLANATION OF PLATE 80. 



Head, eyes, and naked periorbital areas of Columba guinea (mutant and normal) and of other 

 Columba. Colored photographs, Mar. and Apr. 1910. Natural size. Toda del., June 1910. 



A. C. guinea normal (19), adult. Greatest length of naked periorbital area, 27 mm.; greatest width, 15 mm. Color 



nearly blood-red. The pupil is here bordered by two dark spots; there is a smaller one above in addition 

 to the larger one below. (Pupil as seen in shade.) 



B. C. guinea, same as above. (Pupil as seen in sun.) 



C. C. guinea mutant (20), adult. Greatest length of naked periorbital area, 17 mm.; greatest width, 10 mm. The 



red color less intense a plainer trace of gray. Only a trace of an upper dark spot bordering pupil. 



D. Colored photograph of head and neck of C. eversmanni (X 1/1, Toda pinx, June 1910). 



Shows naked space about eye, moderate, greatest length, 20 mm., greatest width, 12 mm.; size intermediate of 

 C. guinea normal and mutant; color, dusky lemon-yellow. Outer iris, dusky red; inner, yellowish-red. Neck- 

 mark lateral, distinct, of few rows; feather-tips with coppery iridescence. 



E. C. domestica. Naked area about eye quite small; nearly slate or horn color. Iris with much red and little (modified) 



yellow. 



F. C. leuconota. Naked periorbital area none, except a little at anterior and posterior angles of eye. The iris is yellow 



with a slight shade of greenish below the pupil, and somewhat in front of the pupil it has a large spot a 

 full 3 mm. long. 



Thus we have in : C. guinea, a plane spot above and below; C. guinea mutant, a very small spot above and a large 

 one below; C. leuconota, none above, but a very large one below. 



