130 Zoological Proceedings of Societies, 



described as inclosing those glands between its fibres. By this arrange- 

 ment the female is enabled to empty by compression the excretory ducts 

 of its mammae, and thus to force their secretions into the mouth of the 

 imperfectly organised young; which, during the earlier periods of its 

 existence appears incapable of extracting a nutritious fluid from that part 

 by the usual means. 



It appears that the secretion of this fluid (milk) takes place only in the 

 larger and lower gland, and that its ejection through the inferior and 

 longer teat is assisted by a muscular investment which incloses the ducts 

 throughout the whole course from the gland to the extremity of the 

 nipple. The existence of this structure has been noticed by M. Geoffroy 

 St. Hilaire, who has assigned to it the same use. Under this compres- 

 sing muscle of the lower (or, as Mr. Morgan has named it, the true 

 marsupial) teat, a congeries of vessels which principally consisted of 

 veins was described as forming a plexus around the central fasciculus of 

 ducts. These veins, together with those of the gland, were stated to 

 occasion a considerable distension of the mammary organ during the time 

 of suckling, in consequence of the congestion which must necessarily 

 occur in the vessels at that period, from the pressure made upon their 

 main trunks by the action of the compresdng muscle of the mamma; 

 for it has been found that the size of the organ on such occasions exceeds 

 that which a loaded state of the ducts only could produce. The mammae 

 were found, as in the virgin animal, to consist in double glands on each 

 side, the upper and smaller presenting the same anatomical characters as 

 in the former instance; its excretory ducts, however, in their course 

 tovrards the upper nipple were found to be inclosed in an indistinct mus- 

 ctilar sheath, and there was a faint indication of the existence of a plexus 

 of vessels similar to that which was found in the lower, or true marsupial, 

 teat. This smaller mammary organ is considered by the authour as 

 analogous to the supernumerary mammae and teats of other mammiferous 

 animals, since the lower or true marsupial mammary glands and their 

 teats appear to perform exclusively the office of preparing a nutritious 

 fluid for the support of the young animal. 



May 24.— This day the Anniversary Meeting of the Society took place, 

 at which Edward, Lord Stanley, v^ elected President, in the room of 

 the late Sir J. E. Smith : Edward Forster, Esq., J. E. Bicheno, Esq., and 

 Richard Taylor, Esq., were respectively re-elected to the offices of 



