. The Quarterly journal of the Geological Society of London. , while a 6 ME. E. T. NEWT0K ON THE OCCEEEEXCE OF [Feb. I904, few of the lower denticles are at right angles with the rest of thecrown. In the British specimen, on the other hand, the loweredge of the enamel is strongly bent, while the lower denticulatedmargin is only slightly curved at its lower end. There is likewisea difference in the denticles ; the Russian specimen having them, asin Edestus minor, double and not triple. Dr. Karpinski was evidently in some doubt as to his specimenbeing really an example of E. minor, for he says t
. The Quarterly journal of the Geological Society of London. , while a 6 ME. E. T. NEWT0K ON THE OCCEEEEXCE OF [Feb. I904, few of the lower denticles are at right angles with the rest of thecrown. In the British specimen, on the other hand, the loweredge of the enamel is strongly bent, while the lower denticulatedmargin is only slightly curved at its lower end. There is likewisea difference in the denticles ; the Russian specimen having them, asin Edestus minor, double and not triple. Dr. Karpinski was evidently in some doubt as to his specimenbeing really an example of E. minor, for he says that it is eitherthis or a closely-allied species, and I am inclined to think that thelatter suggestion is the more justifiable. But, however that maybe, the Smallthorne specimen can scarcely be referred to Edestusminor, the differences mentioned above preventing such a in mind, therefore, the most striking peculiarity of ourfossil, I propose to name it Edestus triserratus. Pig. 2.—Segments of Edestus triserratus restored. (4 nat. size.). A = Anterior, oldest segment. B = Posterior, newest segment. Fortunately the basal portion of our specimen and its trough areso well shown, that the manner in which the segments fittedtogether is obvious ; and, taking advantage of this, the appearanceof half a dozen such segments combined is shown in text-fig. 2. The crowns of all the teeth in Xewberrys figure of E. minor areso nearly of the same size, that one is justified in assuming thatthe teeth and segments of our British specimens did not vary greatlyin this respect, and consequently the combined series would havehad much the appearance of my restoration ; but probably thebasal portions of the older segments of Edestus changed somewhatin shape by continued deposition or absorption of bony first sight it is not clear which is the growing end of sucha series. Among a large number of segments of E. Heinrichsiithat Newberry had for examination was one which pos
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Keywords: ., bookcentury1800, bookdecade1840, booksubjectgeology, bookyear1845
