168 INHERITANCK, FERTILITY, AND SEX IN PIGEONS. 



BREEDING DATA UPON PURE-BRED PIGEONS AND DOVES. 



Some data dealing with various features of the breeding of several species of 

 doves and pigeons are here of interest, not only because they permit comparisons 

 between the results from one and the same species when pure-bred and when 

 crossed, but because they supply additional information on the relation of the 

 order of eggs in the clutch to sex, and on some features of the periods of incubation 

 and egg-production. 



Spilopelia suratensis.—In tables 168 and 169 the results of two long series of 

 matings of Surate turtle-doves (see pi. 24) are given. Both records show almost 

 uniformly "weak germs" from the first and the last eggs of the season; the two 

 pairs were (unequally) overworked. In general the term of life of the offspring is 

 longer in those birds hatched from the eggs of spring and early summer. The pair 

 recorded in table 169 was much "overworked" in comparison with the previous 

 mating, and it will be noted that the much-overworked series is clearly the series of 

 lowest fertility and of shortest average term of life in the offspring. In this much- 

 overworked series all of the eggs of no two successive clutches were able to hatch, 

 except in the early part of the season; here (April 22 to June 18), however, five 

 successive clutches hatched without a failure. 



Stigmatopelia senegalensis. — ^The records for this species are summarized in 

 table 170. In this species there is indicated a decided tendency to produce males 

 from the first egg of the clutch and females from the second. There were 1 1 males 

 from the first and 2 from the second egg. There were 9 females from second eggs 

 and only 2 females from first eggs.^ 



5 The breeding of ChanuEpelia talpicoti (table 172) and of Geotrygon sp. (table 173) furnish little or no data on 

 sex and are of interest only from the standpoint of fertility; 2 pairs (of talpicoti) showed all eggs hatching until late 

 fall; the hatches at this season gave very weak and short-lived oflFspring. — Editor. 



Explanation of Plate 30. 



A. Adult male hybrid (H 1) from a white-'ndnged pigeon and a ring-dove hybrid. One-half natural 



size. Hayashi del., 1901. Hatched April 1, 1901; dead March 5, 190.3. 

 Sire: Melopelia leucoptera. Hatched 4/22/01. A bird of dull dark color with the outer flights of wings white. 

 Dam: St. alba-risoria x risoria-alba X alba; a bird of hght-brown color. 



B. Adult male passenger-pigeon x ring-dove hybrid. One-half natural size. Hayashi del. 



The wing feathers and markings in this hybrid are (June 18, 1905) as follows: 



Tertials, 7: Two inner covered by scapulars. Third exposed, has an obscure, half-washed-out chequer on upper 

 web; this about 15 mm. in length; its distal boundary about 14 mm. from tip of feather. Fourth similarly marked. 

 Fifth has same mark vanishing. Sixth exisosed part is darker than fifth, but there is no mark; i.e. the "brown" of 

 the inner feathers gradually diminishes and becomes more gray and a little darker. Seventh sUghtly less brown 

 and a Uttle darker. 



Secondaries, 6: Eighth to thirteenth have an elongated chequer on lower web, beginning with a length of about 

 24 mm. and extending to within 3 or 4 mm. of tip. The spot grows stronger and longer, becoming about 40 mm., and 

 ending obscurely about 5 mm. from tip on outer secondary, namely the thirteenth feather (including tertial.s). 



Primaries, iO; Fourteenth to twenty-third (counting from inner tertial); a chequer seen on three inner primaries, 

 vanishing on the sixteenth feather (third primary). 



Primary coverts, 10: Second to seventh marked with a short chequer on the lower (outer) web, the mark running 

 to the very tip of the feather. In the passenger-pigeon these feathers are black, hence chequers arise by reducing the 

 basal portions to gray. 



Scapulars: The inner, second longer scapular has a chequer about 20 ram. long on inner half of inner web and 

 reaches to within 12 mm. of the tip of the feather. 



In one hybrid of this derivation these marks were somewhat stronger. They correspond to conspicuous marks 

 in the passenger-pigeon and in the mourning-dove. 



