i3Y D. EMBLETON, M.D. 69 



out is of a more or less green colour, or blue, or yellow, and, it 

 may be, more or less dotted or streaked with blood ; and these 

 last named colours, as the inflammation clears off, are replaced 

 by the normal white of the ordinary secretion. 



The lining membrane of the oviduct of the bird presents the 

 same conditions, and gives out the same secretions, with addi- 

 tions of the lime, etc., as the mucous membrane of the higher 

 animals. The whole oviduct during the laying season is in a very 

 sensitive and excited physiological condition, one bordering on, if 

 not actually and for a time identical with, an inflammatory or 

 pathological state, as are the corresponding parts of the human 

 subject under similar circumstances; and the products, which 

 might be expected to be similar, are, with the exception of the 

 shell of the egg, very much alike. The boundaries between phy- 

 siological and pathological processes are, in some cases, very diffi- 

 cult of definition. 



The lining membrane of the oviduct, supplied as it is with 

 abundance of blood, is then of itself quite equal to the furnishing 

 of all the colours borne by eggs, and it seems unnecessary to have 

 recourse, for the explanation of the presence of these colours, to 

 the hypothesis of special pigment glands in the oviduct, which, 

 glands no one, so far as I know, has ever described. 



In two instances in which I was enabled to examine, during 

 the laying season, the oviduct of the Eook, at the time when an 

 egg had arrived at the lower part of the ''uterus," I have seen 

 intense vascularity of the mucous membrane, distinct ecchymoses 

 in it, and small effusions of blood lying against the ah'cady spot- 

 ted egg, on which the shell had been previously consolidated and 

 finished. 



There can be no doubt as to the above state of the oviduct, and 

 if the tube could have been examined a little earlier, the real 

 connection of the escapes of blood with the spotting of the shell 

 as it was " setting" might very probably have been observed. 



In the case of birds that normally lay white eggs, it may be 

 presumed that the oviduct undergoes the lowest degree of excite- 

 ment incidental to that organ during the breeding season, or tliat 

 its lining membrane and vessels have a strength not existing in 



