470 



CARNIVORA. 



penetrate the side of the sac, and so become 

 extensively diffused through the surrounding 

 cellular membrane, involving the whole anterior 

 and lateral portions of the joint. In such a 

 case the practitioner is very liable to be de- 

 ceived as to the true character of the abscess, 

 and to confound it with those which originate 

 in the cellular membrane. 



There are certain cases in which acute inflam- 

 mation of a bursa becomes even a more serious 

 disease than that just alluded to. In the syno- 

 vial sheaths of the flexor tendons, for example, 

 the progress and termination of the inflamma- 

 tion are often modified in a remarkable manner 

 by the anatomical peculiarities of that part. In 

 that form of the paronychia affecting the ante- 

 rior part of the finger, and seated in the synovial 

 sheath of its flexor tendon, the inflamed mem- 

 brane is closely bound down by a dense and 

 unyielding fibrous layer : hence not only death 

 of the contained tendon may be produced, but 

 even extension of the disease to the bone itself. 

 Such are the morbid changes usually met 

 with in the contents of inflamed buisae; but if 

 the disease have been of long standing, changes 

 scarcely less remarkable are produced in the 

 structure of the bursa itself. Instead of the 

 delicate synovial membrane we have above 

 described, it is frequently found converted into 

 a firm gristly substance, sometimes half an 

 inch in thickness. In such cases no tact, how- 

 ever delicate and experienced, could, previously 

 to operation, have detected the presence of 

 matter. 



Monro seems to regard, in certain cases at 

 least, the communication above alluded to be- 

 tween certain bursae and the neighbouring joints 

 as the result of rupture or of friction : he even 

 considers it remarkable that in such instances 

 neither lameness nor pain had been complained 

 of during the lifetime of the individual. It ap- 

 pears to us, however, much more probable that 

 in those instances the synovial membrane of the 

 joint and that of the bursa have been ab initio 

 but different parts of one and the same structure ; 

 at least, in our dissections of the subcrureus 

 bursa in young subjects, we have more than 

 once observed it communicating freely with 

 the joint. 



For Bibliography, see that of SYNOVIAL MEM- 

 BRANE. 



(John E. Brenan.) 



CARNIVORA (euro, carnis, and voro,) an 

 interesting and highly important group of the 

 mammifera, constituting the typical order of 

 that great division of the class which feed 

 upon animal aliment. Whether the present 

 group can with propriety be considered as en- 

 titled by its organization to the ordinal rank 

 which we have assigned to it above, or whether 

 it does not rather form a subdivision of a great 

 order, answering nearly to the Carnassiers of 

 Cuvier, is a question which, as it is variously 

 viewed by different naturalists, may be safely 

 left undecided in a work like the present, in 

 which structure rather than arrangement is the 

 principal object of research, and in which the 

 nomenclature of a system is of little importance, 



compared with the developement of anatomical 

 and physiological truth. The Carnassiers of 

 Cuvier (excluding the Marsuplata, which may 

 unhesitatingly be considered as a distinct 

 order,) includes a natural and tolerably well 

 defined assemblage of animals, to which the 

 term ZOOPHAGA may with propriety be applied 

 as the classical equivalent to the French phrase 

 of that distinguished zoologist; but however 

 the stricter rules of zoological arrangement may 

 render it difficult to divide this group into the 

 three orders of CHEIROPTERA, INSECTIVORA, 

 and CARNIVORA, it has appeared to the 

 author of this essay as more convenient on 

 the present occasion to assign that designation 

 to each of these divisions, and to make the 

 structure of each the subject of a separate 

 article. 



The characters of the Carnivora as distinct 

 from the rest of the digitate animals possessing 

 the three distinct classes of teeth, (which, be- 

 sides the other Zoophaga., include the Quadru- 

 mana and the Marsupiata,) are such as point 

 them out as especially formed for the pursuit 

 and destruction of vertebrate animals. They 

 possess in the upper and in the lower jaw six 

 incisive teeth, a large, strong, and pointed ca- 

 nine tooth on each side, and molar teeth which 

 partake in a greater or less degree of the charac- 

 ters distinctive of the class, according to the 

 habits of the different genera. These molars con- 

 sist of three distinct kinds: the anterior, which 

 immediately follow the canine, are more or less 

 pointed, and are termed false molars ; the next 

 class, formed especially for cutting in pieces 

 the flesh on which the animals feed, are termed 

 by M. Frederick Cuvier Carnassiers; and the 

 posterior are tuberculated. The proportion 

 which these different classes of teeth bear to 

 each other in number or developement, accords 

 with the degree of the carnivorous propensity 

 in the animal. 



In agreement with these characters of the 

 teeth, the feet are digitate, the toes furnished 

 with claws, which in some are retractile ; the 

 stomach is simple, the intestines are short, and 

 the ccDcum is either very small or altogether 

 wanting. 



The animals of this order differ in the form 

 and position of the posterior feet ; in some, 

 hence termed plantigrade, the whole foot rests 

 on the ground ; in others, called digitigrade, 

 the toes only touch the ground, the heel being 

 considerably raised. Of the former structure 

 the bears exhibit the type, and the cats of the 

 latter. A third and most remarkable form of 

 the extremities is shown in the Seal tribe, in 

 which the anterior as well as the posterior feet 

 are formed for swimming, being spread into fin- 

 like paddles. 



The families of which this order is com- 

 posed are perhaps as follow : 

 \ . URSID^E, typical genus Ursus, bear. 



2. MUSTELID^;, do. Mustela, marten. 



3. CANID-&, do. Cam's, dog, wolf. 



4. FELID^;, do. Felis. cat. 



5. PHOCID.E, do. Phoca, seal. 



Of these families the FELID^ constitute the 

 type of the order, possessing the carnivorous 



