4. Journals. The student should consult the numerous papers by Prof. Marsh in _The American Journal of Science_; and by Prof. Cope in _The American Naturalist_. Many of Prof. Marsh's papers have also appeared in _The Geological Magazine_ and in _Nature_. The two latter journals contain many other valuable papers (and reviews of Monographs, etc.), too numerous to be separately mentioned. Some are referred to in the text. _The Quarterly Journal of the Geological Society_ contains many papers on Extinct Animals. See also papers in _Natural Science_ and _Knowledge_. APPENDIX V. ICHTHYOSAURS. [Illustration: Fig. 59.--_Ichthyosaurus tenuirostris_, from Würtemberg.] It was unfortunate that news of the highly interesting discovery at Würtemberg came too late for our artist to make a new drawing for our first edition, to show the dorsal fin and large tail-fin, etc., described by Dr. Fraas.[82] This has now been done, as shown in Plate II. By the courtesy of the proprietors of _Natural Science_, we are enabled to reproduce two drawings (Fig. 59) from the September number, illustrating a paper by Mr. Lydekker, in which he gives a _résumé_ of the latest intelligence with regard to Ichthyosaurian reptiles. [82] Ueber einen neuen Fund von _Ichthyosaurus_ in Würtemberg. _Neues Jahrbuch f. Mineralogie_, 1892, vol. ii. pp. 87-90. The same author has published a valuable monograph, with beautiful plates, entitled _Die Ichthysaurier der Süddentschen Trias- und Jura-Ablagerungen_. 4to. Tübingen, 1891. In the present year (1892) there has been discovered in the Lias of Würtemberg the skeleton of an Ichthyosaur, in which the outline of the fleshy parts is completely preserved (see lower figure). The reader will see from the figure that the tail-fin is very large, and the backbone appears to run into the lower lobe. Such a tail-fin as this impression indicates must have resembled that of the shark's, only it is wider; but the shark's backbone runs into the _upper_ lobe. Sir Richard Owen long ago foretold the existence of this appendage, and the discovery, coming now (when his life is despaired of), adds one more tribute to his genius. Behind the triangular fin on the back comes a row of horny excrescences reminding us of those of the crested newt.