184- Natural History in London, 



except of such rare animals as can seldom, if ever, be brought alive to Eu- 

 rope. Skeletons, exhibiting the structure and distinctive characters of the 

 orders and genera, accompanied with correct coloured drawings of the species, 

 arranged in frames, would be far more durable, and convey more scientific 

 information than stuffed specimens ; they would occupy less space, and also 

 be less expensive. 



^ A slight inspection of the rooms in the Museum, appropriated to natural 

 history, will prove that the science has outgrown the space allotted for it. 



It is much to be desired that ample room may be found in the buildings 

 now erecting, to exhibit properly the objects in every department of nature, 

 and that our national museum may be placed on a par with the museums of 

 natural history on the Continent. We may also be permitted to express a 

 ■wish, that no unnecessary delay in completing the arrangements may be 

 tolerated. It would add greatly to the utility of the collections, if, beside 

 the general catalogue at present published, an ample systematic catalogue 

 were also to be published, for the use of those who are commencing the 

 regular study of natural history. 



Linnean Society. — May 4. TheVeading of Mr. Morgan's paper, on the 

 mammary organs of the kangaroo, containing farther particulars of the dis- 

 section of these parts, as well as of the muscles attached to the marsupial 

 bones, in the adult and impregnated animal, was continued. These bones, 

 with their ligamentous and muscular connections, were described, and seve- 

 ral errors in Sir Everard Home's published account of these parts were 

 pointed out. The author then stated his own opinions respecting the use 

 of these structures. He stated that the marsupial bones are formed, first, 

 for the purpose of giving that firm support to the superincumbent abdomi- 

 nal viscera which the narrow pelvis of the animal is incapable of affording, 

 while in the erect posture ; and, secondly, for the purpose of constituting a 

 fixed point of resistance, against which the mammae are squeezed by the 

 muscular girdle already described as enclosing those glands between their 

 fibres. By this arrangement, 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 (or 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 their 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 compressing 

 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 de- 

 scribed as forming a plexus around the central fasciculus of ducts. These 

 veins, together with those of the gland, were stated to occasion a consider- 

 able distension of the mammary organ during the time of suckling, in conse- 

 quence 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 

 compressing muscle of the mammae ; 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 ani- 

 mal, to consist in double glands on each side, the upper and smaller pre- 

 senting the sam'e anatomical characters as in the former instance ; its excre- 

 tory ducts, however, in their course towards the upper nipple, were found 

 to be enclosed in an indistinct muscular sheath, and there was a faint indi- 

 cation 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 con- 

 sidered by the author as analogous to the supernumerary mammae and teats 

 of other mammiferous animals, since the lower, or true, marsupial mammary 



