448 



MANUAL OF HISTOLOGY. 



deserves to be mentioned, is " the presence in the cavities of 

 the acini of a peculiar granular material, the coagulated con- 

 dition of a fluid." Partsch has also described the occurrence 

 of this granular mass within the alveoli, and he states that the 

 secreting epithelia, though of normal size, were furnished with 

 shrunken nuclei, and showed numerous light spots, as if the 



cells were perforated and sieve-like. It 

 would appear that this writer has ob- 

 served the stage of vacuolation with- 

 out, however, interpreting the same in 

 Creighton's sense. 



Creighton also describes in certain 

 glands the connective-tissue stroma as 

 crowded with cellular elements, which 

 he considers equally with the pigmented 

 corpuscles as waste-cells of the secre- 

 tion. Others (Winkler, Brunn, and par- 

 ticularly Rauber) have assigned a far 

 different significance to these bodies, as 

 will appear farther on. Finally, Creigh- 

 ton explains that the secretion of the 

 mammary gland " may be said to be pro- 

 duced by a transformation of the sub- 

 stance of successive generations of 



epithelial cells, and in the state of full activity that transfor- 

 mation of the substance is so complete, that it may be called a 

 deliquescence." 



Although Creighton's investigations did not extend to the 

 human mammary gland, there is ample ground for the belief 

 that changes of evolution and involution similar to those which 

 he has described in animals, constantly take place in the hu- 

 man female as well. And even if we accept only some of his 

 views on the inter-relations of physiological action and histo- 

 logical appearance, the discrepancy still existing in the de- 

 scriptions given by different authors will receive a more rational 

 explanation than has hitherto been offered by writers on this 

 subject. Certainly some of his assertions appear rather fanci- 

 ful in their far-reaching novelty, nevertheless they deserve the 

 attentive consideration which we have, at least, in part bestowed 

 on them. 



From the results of our own examinations, we are unable 



FIG. 195. Acini from a partly 

 expanded gland, some of them 

 filled with a granular material. 

 From the mamma of a pregnant 

 cat. Creighton. 



