OCR Text |
Show 1892.] NUMERICAL VARIATION IN TEETH. 109 class, though the materials which support this view cannot easily be given in brief. Partial or complete reduplication of teeth occurring in the second way was seen in P. grcenlandica (pj), Otaria cinerea (m1), Canis me-somelas (p3), Vison horsfieldii (p»), Herpestes orient alls (p2), Herpestes gracilis (tf), Felis domestica (p4), ditto (p1), Phalanger orientalis Q?), &c. The power of a single organ to reproduce itself is of course not confined to teeth, but will be shown to be present in many different kinds of organs, and especially in those which are arranged as a Series of Multiple Parts. Variation in Terminal Teeth when a new member is added to the series. This is a phenomenon which is most instructive as a guide to the Fig. 3. Canis azarce, from specimens in the Leyden Museum. I. Right upper molars of a specimen having a supernumerary third molar on each side. II. The right lower jaw of the same. III. and IV. The right upper and lower jaws of a normal skull of rather larger absolute size, to show the increased size of the teeth in the abnormal specimen. C. The carnassial tooth. nature of the process by which Multiple Parts are formed. It may be stated generally that if the tooth which is the last of a normal |