653 



MAMMALOGY. 



MAMMARY GLANDS. 



651 



e. Cenina. 

 Muntjacus, Gray. 



Stylocerus, H. Smith. 



Cerculus, De Blainv. 



Prox, Ogilby. 

 Coassus, Gray. 



Subula, H. Smith, Lesson. 

 Cariacus, Gray. 



Mamma, H. Smith (not Rafin.). 

 Capreolm, Brisson, Gray,H. Smith 

 (not Ogilby). 



Caprea, Ogilby. 

 Cervug, Linn, 



Kliiphtu, H. Smith. 

 Axis, H. Smith, Ogilby. 

 Kitsa, H. Smith, Hodgson. 



Rucemus, Hodgson. 



Jlippelapkus, Gray. 

 Peudocervus, Hodgson. 

 Panolia, Gray. 



Dama, Gray, H. Smith (not 

 Bennett). 



Ibmr/ifer, H. Smith. 



', Gray, Ogilby. 

 : II. Smith, Ogilby. 



Family 2. 

 Equtu, Linn., Gray. 

 Asimu, Gray. 



** Belliue ai,d Bruia, Linn. 



Family 3. Elepli'nit'i<l:r. 



". Kit ill" * iiiini. 



Elephai, Linn. 

 Loxodonta, F. Cuv. 



6. Tapirina. 

 Tapinti, Brisaon, 

 Tapir, Zimmerman. 

 Khinofhcerus, Wagler. 



c. Suina. 



Sia, Linn., F. CUT. 

 Babirussa, F. Cuv. 



Porcu, Wagler. 



Suclcoteirut (?), Shaw. 

 Koiropolamta, Gray. 

 Phafcochotrui, Cuv. 



Eureodon, G. Fischer. 

 Dicolylei, Cuv. 



w, G. Fischer. 



rf. Rhinocerina, 

 Rhinoceros, Linn. 



Hyrax, Henn. 

 Lipura, Illiger. 

 Cavia, Pallas. 



e. Hippopotamina. 

 Hippopotamus, Linn. 



Family 4. Dasypidce. 



a. Manina. 

 Manig, Linn. 



Pamphractus, Illiger. 

 Pholidotus, Brissou. 

 Pangolinus, Raf. 

 Phatigintu, Raf. 



J. Dasypina. 



Datypiu, Linn. 



Tolypeutes, Illiger. 



Cataphracta, Storr. 

 Daaypui, Linn., F. Cuv. 



Armadillo, Brisson. 

 Tatunia, F. Cuv. 



Euphractm, Wagler. 

 Xenurus, Wagler. 

 Priodontes, F. Cuv. 



Prlonodon, Gray (not Horsf.). 



Chttoniscus, Wagler. 

 Chlamyphnrus, Harlan. 



c. Oryrteropina. 

 Orycteropua, Geoff. 



d. Myrmecophagina. 



Myrmecophaga, Linn., Gray. 

 Tamandua, Gray, F. Cuv. 



Uroleptei, Wagler. 

 Cydothwu, Gray. 



Myrmydon, Wagler. 



Didactylit, F. Cuv. 



e. Ornithorhynclint". 

 Platypus, Shaw. 



Ornithorhynchui, Blum. 

 Dtrmipe*, Wiegm. 

 Echidna, Cuv. 



Tacliyyloiiui, Illiger. 



Family 5. 

 Cholceptu, Illiger. 



Bradypus, F. Cuv. 

 Bradyput, Linn., Illiger. 



Tardiyradus, Brisson. 



Arctopitheciu, Gesner. 



Achaia, F. Cuv. 



Mr. Swainson, who does not admit Man into the zoological circle for 

 reasons stated in his ' Natural History and Classification of Quadrupeds' 

 (1836), gives in the third part of his book an arrangement of ' the Class 

 Mammalia, according to its natural affinities.' He makes the Quad- 

 rumana, the first order, consist of the following families : \,Simiadee. 

 2, Cebida. 3, Lemurida. 4, Veipertilionidff, consisting of Dr. Gray's 

 sub-families Rhinolophina, Pkylloitomina, Pteropina, Noctiltonina, and 

 Venpertilionina. 



The second order, Fere?, includes the families 1, Felida. 2, Mas- 

 telida, consisting of the sub-families Viverince ( Viverrina), Mvxtdinas, 

 and Urrinn. 3, DidelpTiida (Opossums). 4, Soretida. 5, Phocidee. 



The third order, Cetarea, comprehends the families 1, >V,Y /,/'</ 

 (Herbivorous Cetacea). 1, Cete, with the sub-families Delphirwe and 

 Battfninai (?). 



The fourth order, Ungitlata, embraces Tribe 1, Pachydermea. 

 Tribe 2, A noplotheres. Tribe 3, Edentate*, including the Monotremes. 

 Tribe 4, Rinninn.nte (comprehending the families 1, Honda. 2, 

 Antilopiflir. 3, C'em'tlte. 4, Motchidce. 5, Camelopard<e). Tribe 5, 

 Snlipeda. 



The fifth order, Glim, consists of Division 1, Glirea proper, with 

 clavicles. Division 2, Clavicles rudimentary or none. 



Immediately following the genus Cariti and its sub-genera we find 

 the ' Marsupial Rwlentia, situation uncertain ;' and next to them the 

 family ' Afartnpidtc' (Herbivorous Marsupials), formed of the genera 

 Htilmatiifiu, BfptmrfauHU, and P/<'ilri>iglxtri, thd latter with two 

 sub-genera, Petaaritta and Peltmrits. 



The works of Buffon can hardly be said to present any principle of 

 classification as applicable to the Mammalia. Pennant indeed gives 

 what he calls a systematic index of the genera, species, and varieties, 

 and divides th Quadrupeds into two grand divisions (the first without 

 a name, and including: !, Horse; 2, Ox; 3, Sheep; 4, Goat; 5, 

 Giraffe; 6, Antelope; 7, Deer; 8, Musk ; 9, Camel ; 10, Hog; 11, 

 Rhinoceros; 12, Ilippopotame; 13, Tapir; 1 4, Elephant, ai generic 



appellations : and the second grand division, with the name of Digi" 

 tated Quadrupeds, including the genera (Section 1) 15, Ape; 16> 

 Macaueo; (Section 2) 17, Dog; 18, Hyjena ; 19, Cat; 20, Bear; 

 21, Badger; 22, Opossum ; 23, Weasel; 24, Otter; (Section 3) 25, 

 Cavy; 26, Hare; 27, Beaver; 28, Porcupine; 29, Marmot; 30, 

 Squirrel; 31, Jerboa; 32, Rat; 33, Shrew; 34, Mole; 35, Hedgehog; 

 36, Sloth; 37, Armadillo ; 38, Mauis ; 39, Ant-Eater; 40, Walrus; 

 41, Seal; 42, Manati; 43, Bat); but this catalogue can hardly be 

 called systematic. In his later editions he formed his catalogue into 

 a more complete ' Method,' with four grand divisions: 1, Hoofed 

 Quadrupeds; 2, Digitated; 3, Pinnated; 4, Winged; but his work 

 will always be consulted more for the natural history of the ' Quad- 

 rupeds ' there treated of than for their arrangement. 



For further information the reader must consult the works of 

 Pallas, Allamand, Schreber, Shaw, Marcgrave, Catesby, Hernandez, 

 D'Azara, Sonnerat, Steller, Sparrman, Le Vaillant, Bruce, Barrow, 

 Burchell, Humboldt, Peron, Lesueur, Fischer, Lesson, Riippell, Smith, 

 Richardson, Bennett, Bell, Owen, Ogilby, Sykes, Darwin, and a host of 

 others, who have enriched the subject by their writings or the obser- 

 vations which they have made in their travels. 



MAMMARY GLANDS, LACTEAL GLANDS, or MAMMAE, are 

 organs of considerable interest from their occurring ouly in that 

 important class of animals to which they give a name [MAMMALIA], 

 and whose greatest peculiarity is that, while young, their food is the 

 milk secreted by the mammary gland of their mother. 



The number of mammary glands varies in different animals. They 

 are composed of ramified ducts which open on the surface of a nipple 

 or teat by a very minute orifice. In some animals, as ruminants, 

 there is but one orifice at the extremity of each nipple < in others, and 

 in man, there are several. Each orifice leads into a fine canal, which 

 however soon dilates, and ramifies with irregular and tortuous branches 

 in the substance of the breast or udder. Each branch has either a 

 simple closed extremity or terminates in a minute cellule, and nume- 

 rous capillary blood-vessels ramify on their walls and secrete the 

 milk into them. When the mouth of the young animal, by the action 

 of sucking, produces a partial vacuum over the nipple, the weight of 

 the surrounding medium presses lightly and equally upon the surface 

 of the breast or udder, and propels the milk from the ducts in minute 

 and gentle streams. 



With respect to their structure, the lacteal glands, in all essential 

 particulars completely correspond with the larger racemose glands, 

 for instance, the parotid and the pancreas. Each gland consists of 15, 

 24, or more irregular flattened lobes, \" to 1" wide, with a rounded, 

 angular outline, which, although their cavities are quite distinct from 

 each other, eannot externally always be definitely separated. Each- is 

 composed of a certain number of smaller and smallest lobules, and 

 these lastly of gland-vesicles. The latter are rounded or pyriform, 

 0'05'" 0'07'" in size, with a distinct construction between them and 

 the smallest excretory duct, as for instance in the small mucous 

 glands, and as everywhere else are formed of a structureless membrane 

 and tesselated epithelium, which at the time of lactation undergoes 

 peculiar metamorphoses. All these glandular elements are surrounded 

 by dense white connective tissue, particularly abundant between the 

 gland vesicles and smaller lobules, and are united into a compact large 

 glandular mass, which is ultimately covered by a quantity of adipose 

 tissue, or in part by the skin. The lacteal glands are properly 

 speaking not simple glands, but like the lachrymal, aggregations of 

 these. From each glandular lobfi by the coalescence of the excretory 

 ducts of the smaller and larger lobules, there ultimately proceeds a 

 shorter or longer duct, 1'" 2'" in diameter, the lacteal duct or 

 canal (ductus lactiferus or galactophorus), which 'running towards 

 the nipple dilates beneath the areola into an elongated sacculus, 

 2"' 4'" wide, the lacteal sac or receptacle (sacculus or sinus lacti 

 ferus), afterwards coutracting to 1'" or J'" it bends round into the 

 nipple, and ultimately opens at its apex, in an independent orifice, 

 not, more than J'" '" in diameter, between the papilla; that exist 

 in that situation. All these excretory ducts, besides an epithelium, 

 which in the largest of them presents cylindrical cells 0'006'" O'OOl'" 

 long, and in the finer ramifications rounded polygonal smaller cells, 

 and a homogeneous layer beneath them, also possess a white dense 

 fibrous membrane longitudinally plicated in the larger canals, in which 

 hitherto no muscular fibres have been discovered, nothing but a 

 nucleated longitudinally fibrous connective tissue, with fine elastic 

 fibres. Heule however more recently thinks that he has noticed 

 longitudinal muscles in the lacteal ducts ; not those of the nipple, but 

 more deeply within the gland. 



The nipple (mamilla) and the areola present numerous smooth 

 muscles to which the contractibility of those parts is owing. The 

 bloodvessels of the lacteal glands are numerous, and surround 

 the gland'Vesicles with a rather close plexus of capillaries. The 

 veins in the areola constitute a circle which is not always quite 

 complete. The lymphatics are equally abundant in the skin covering 

 the gland, whilst in the gland itself they have not yet been demon- 

 strated. The nerves of the skin covering the mamma are derived from 

 the supraclavicular nerves, and the cutaneous branches of the second, 

 third, and fourth intercostals. In the interior of the gland no other 

 nerves can be traced than a few fme twigs accompanying the vessels, 

 whose termination is unknown. 



