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Show 1016 MESSRS. B. C. A. WINDLE AND F. G. PARSONS ON [Dec. 19, common to the two animals, such as the total absence of fabellae from the gastrocnemius, the occasional presence of a fibular origin for the extensor brevis digitorum pedis, and the absence of the sterno-facialis (sphincter colli) part of the panniculus, which are not so striking as the former two, but which, taken together, are enough to make us think that there is a closer kinship between the Sloths and the Pangolins than they are generally supposed to possess. It would be easy to pick out points of similarity between the Sloths, Ant-eaters, and Armadillos by reason of which they differ from the generalized mammalian type, and which clearly point to their near relationship with one another; it would also be easy to indicate by means of its muscles that, although Manis cannot be a very distant relation of the Bradypodidce, it is more closely allied to the Myrmecophagidce and Dasypodidce. W h e n we come to consider the Orycteropodidce, however, we are more struck with the generalized mammalian arrangement of its muscles than by any special edentate characteristics : the three points on which we laid so much stress in claiming a place for the Pangolins in the Edentate order are wanting in the Aard-vark. There is no rectus thoracis lateralis, no femoral head to the flexor cruris lateralis, and it has fabellae in its gastrocnemius just like any other mammal. In addition to this the sterno-facialis, which in all other Edentates is suppressed, is very strongly marked and covers a part of the pectorals as in Erinaceus among the Iusectivora and Bathyergus among Eodentia. There are, however, a few points in which the Aard-vark differs from most mammals and resembles the Edentata. One of these is the presence of more than one scapular bead for the extensor cubiti (triceps), and another is the double tibialis posticus. W e have never yet seen either of these arrangements in any other mammals but the Edentates; and we cannot help regarding this animal as a link between the Edentates and the more generalized stock from which that order has diverged. We have read with much interest a paper by Dr. Elliot Smith (Trans. Linn. Soc, 2nd ser. Zool. vol. vii. pt. 7, p. 387) in which he says that " if the brain of Oryeteropus were given to an anatomist acquainted with all the other variations of the mammalian type of brain, there is probably only one feature which would lead him to hesitate in describing it as an exceedingly simple Ungulate brain." Changing the word muscles for that of brain, this is practically our own view. There are only one or two points which would cause us to hesitate in describing Oryeteropus as a generalized type of mammal, but these one or two are certainly in an edentate direction. We further read (ib. p. 390) that Manis has certain cerebral features which point to a relationship with the American Edentate group; a statement which strongly confirms the view which we have already expressed. Taking all these facts into consideration, we think that the systematists do well to retain the order of Edentata, although the name is certainly a misguiding appellation. W e also think that it is not wise to lay too much stress on the articulations of the |