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limbs) has reference rather to the adaptation of the creature to its external life 

 than to the general plan of its structure. The division leads to a confusion 

 which has become manifest in the light of the more advanced science of the 

 present day. The whale tribe (Cetacea) with their high mammalian 

 organisation, appear unduly degraded to the very bottom of Cuvier's table, 

 merely because the wants of a purely marine habitat have been met by a 

 development of the caudal extremity of the vertebral column, which supersedes 

 the necessity for a development of the posterior limbs. On the other hand 

 the Ornithorynchus (order Monotremata), whose structure presents marked 

 analogies to the oviparous vertebrates, is elevated, merely in virtue of its clawed 

 extremites, to a place above the Elephant and Horse. Yet, as Owen remarks, 

 " no one has proposed to associate the unguiculate Bird or Lizard with the 

 unguiculate Ape ; and it is but a little less violation of natural affinities to 

 associate the Monotrenes with the Quadrumanes in the same primary (unguicu- 

 late) division of the mammalian class." Again Cuvier's secondary division 

 according to the structure of the teeth is open to the same objection, and leads 

 through, in a less degree, to the same inversion of Natural order, and con- 

 fusion of Natural affinity. The possession by the Kangaroo of three kinds of 

 teeth, elevated the genus, in Cuvier's list, to a place intermediate between the 

 Carnivora and Roclentia, removing it from its true association with that other 

 strange Australian already mentioned, the Ornithorynchus ; which as wanting 

 canine teeth and incisors, was ranked with South American types, the Armadillo, 

 Sloth, and Ant-eater. The superiority of the more modern method, as a 

 ground of classification, is best made evident in the case of the rudimentary 

 organs. These would seem to the Teleologist but as " freaks of nature ;" whilst 

 to the eye of Morphology they are characters of the utmost significance. Thus 

 Dr. Carpenter writes : — " "We find, as might have been expected, * * that 

 if the plan of structure in a particular tribe involves the wcm-development of 

 some organ which is possessed by neighbouring groups, its conformity to 

 archetypal regularity is generally manifested by the presence of that organ in 

 a rudimentary, or undeveloped condition. Thus, we find some rudiment of 

 the lung in most Fishes, even where it is not sufficiently developed to serve as 

 an 'air-bladder' in regulating the specific gravity of the body. In the 

 abdominal muscles of Mammals, again, we find the abdominal sternum and 

 ribs of Saurian Reptiles indicated by white fibrous bands ; and in those 

 Mammals which do not possess a clavicle, that bone is usually represented by 

 a ligament, just as the stylo-hyoid ligaments in Man represents a portion of 

 the hyoiclean arch which is elsewhere [i.e., in others of the Mammalia] com- 

 pletely ossified. Such rudimentary structures, however, often display them- 

 selves only at an early period of development, and are subsequently lost sight 

 of. Thus the rudiments of teeth, which are never developed, and which, at a 

 later period cannot be detected, are found in the embryo of the Whale, both in 

 the upper and under jaws ; and Professor Goodsir has ascertained that the 

 rudiments of canine teeth, and of the incisors of the upper jaw, which are not 

 subsequently developed, exist in the embryos of Ruminating Mammals. The 

 most remarkable example of the kind, however, is the existence of branchial 

 arches, resembling those of the Fish, in the early embryo of all air-breathing 

 Mammalia." In the Vegetable kingdom the same conformity to a common 

 type is manifested by the presence of rudimentary organs. In the common 

 Sage, for example, " we find only two stamens where the general plan of the 

 flower would lead us to expect five ; but upon looking attentively at the 

 interior of the corolla, two little scales are often to be seen growing in the 

 place where two of the deficient stamens should have been ; these two scales 

 are frequently developed as perfect stamens in flowers which are otherwise 

 constructed precisely like the sage ; and even the fifth makes its appearance in 



