84 • A rAri:u ox Ktius. 



this paper was written, Mr. John Hancock kindly lent me the 

 work of F. A. L, Thicneman, M.D., entitled, ^' Si/stemafi.'ichfi 

 Barstellung der Foripflan-jing der Vdgel Europa's mit AhhiJdung 

 der Eiery Leipzig, -ito, 1825-38. 



In the introduction, p. 1, we find the following passage, which, 

 with others here quoted, I have translated as literally as possible. 



'' The egg is round in the ovarium, but owing to the pressure 

 it has to undergo in the oviduct, it must there become elongated. 

 That part which first enters that tube, as a rule, becomes the 

 pointed end, for it has to open out the road, and experiences the 

 greatest opposition. The degree of pressure, however, depends 

 upon the condition of the oviduct, and other incidental circum- 

 stances which so operate, that no egg has exactly the form of 

 any other, though each species of bird has certain peculiarities 

 which are not entirely lost, though many minute differences 

 occur. 



"If an egg passes rapidly down the o\'iduct it becomes much 

 elongated and has no hard shell on it, as may be seen in the case 

 of hens which, soon after the egg has passed into the oviduct, 

 have been much chased about, the long diameter of the egg is 

 then six to eight times greater than the transverse. 



*' If the egg goes slowly down the oviduct and becomes per- 

 fected and overlaid with a hard shell, it is shorter." 



At p. 9. — " The egg when laid is more or less moist, and has 

 often upon it fresh blood spots and streaks which it has derived 

 from the cloaca." 



At p. 11. — " The colouring of eggs goes on during the forma- 

 tion of the calcareous slull, and this in two ways. Either the 

 whole shell is mixed throughout with colouring matters, and 

 these are greenish, or yellowish, or brownish ; or, through the 

 pressure of the egg on the swollen blood vessels of the o\-iduct, 

 the i)ent up blood becomes discluirged mechanically, sinks in 

 more or less upon the soft or hardening shell mass, and gives 

 the streaks or spots, 



"This conditionates tlie indefiniteness of tlu* pattern, so tliat 

 eggs are never produced alike ; the state also of the vessels is 

 not ahvavs the same, and there is a difference too in the shell. 



