DEPARTMENT OF EXPERIMENTAL EVOLUTION. 87 



urged by our colleague, Dr. Castle, the germ-gland has been removed from 

 a horned ewe lamb and from a horned ram lamb. It is also planned to 

 make studies on castrated rams on farms near by. The experiments seem 

 worth while in order to bring under a general rule the outlying case of 

 horns in sheep. 



SEX STUDIES IN POULTRY. 



A fourth series on this subject treats of the interrelation of sex-glands 

 and somatic coloration. Poultry, like birds in general, are markedly di- 

 morphic in coloration. Mr. Goodale removed the left ovary (which alone 

 normally functions) from a duck that was 12 weeks old. This bird con- 

 tinued to develop female plumage for more than a year, but finally acquired 

 so much of the plumage of the male as to be easily mistaken for such. 

 Autopsy revealed the fact that the removal of the ovary was complete and 

 the right gland was also lacking. The only oviduct was the normal left one 

 and that was in a juvenile condition. Thus this bird that had gained the 

 male plumage was an unsexed female. Another case of even greater inter- 

 est, also worked out by Mr. Goodale, is that of a Brown Leghorn female 

 from which the left ovary was removed when the bird was less than a 

 month old and which assumed most, but not all, of the characters of the 

 male. When the bird was about a year old an autopsy was made and, in 

 place of the removed ovary and on the right side also, there was found a 

 small organ, sections of which showed a mass of cells that were undifferen- 

 tiated and very different from those of the normal testis. Both vasa deffer- 

 entia were present, but not functional, and a well-developed but juvenile ovi- 

 duct was present on the left side. Mr. Goodale has repeated this experiment, 

 which seems well calculated to demonstrate the essentially hermaphrodite 

 nature of the female fowl. 



From some Brown Leghorn males of the age of three weeks testes were 

 removed by Mr. Goodale. All developed the usual secondary male char- 

 acters of plumage and spurs. The comb, on the other hand, developed far 

 less than on the hen of the same race, so that the small comb of the capon 

 can hardly be considered a female character. The crowing and mating in- 

 stincts also are lacking. 



Spurred Hens. — Spurs are secondary sex characters of cocks. Occasion- 

 ally they are found even on young hens. In order to learn if the tendency 

 to hen-spurring is inherited, three such hens were mated, by Mr. Goodale, 

 to a cock that belonged to the same strain as one of the hens. Though the 

 progeny are still too young to show spurs, the positive result has been gained 

 that a hen with spurs need not differ, in point of fecundity and full develop- 

 ment of maternal instincts, from ordinary non-spurred hens. 



SEX IN MOLDS. 



To broaden our knowledge of the phenomena of sex, Dr. A. F. Blakeslee, 

 botanist at the Storrs Agricultural Experiment Station, well known for his 

 researches in sex of the molds, has been granted leave of absence from 



