X.
| Case. | Comp. | Tablet. | Specimen. |
| J | c | 14 | 1, 2 |
Ornithocheirus Fittoni (Owen).
The fragment is 11/2 inch long, with two large elliptical tooth-sockets on each side of the flattened palate, and one pair in front. The third socket is separated from the fourth by a considerable interspace. Between the third sockets arises the median palatal ridge, and from the inner margin of each socket a lateral ridge appears to be continued. Behind the third socket the jaw measures 11/16ths of an inch from side to side, and 10/16ths of an inch high. The sides converge and round convexly into each other. The jaws appear to have been long; It is only known by upper jaws. The type specimen shows the socket of another tooth in front of the last one figured by Prof. Owen. It is directed outward at a greater angle, and separated from the hinder one by a wall not 1/16th of an inch thick, and the teeth of this pair must have been parted from each other by a film equally thin. There is no truncation of the snout as in O. Woodwardi.
Another specimen shows some variations. This fragment of a premaxillary bone is fractured through the third pair of tooth-sockets in front and through the seventh pair behind. It is about 21/8th inches long; the palate is 11/16ths of an inch wide behind the great tooth, and maintains the same width. The jaw is 11/16ths of an inch high behind, and 10/16ths high in front. The sides are gently convex, and imperceptibly unite to form the well-rounded depressed mesial ridge of the beak. From the front of the third to the back of the fifth socket measures 13/8ths inch. The sockets are ovate, rather smaller, and closer together than in the type of O. Fittoni; margins elevated. The variations from types are so many, and often so considerable, as to suggest the idea that the fossil groups called species may in the living animals have often been genera.
In all the specimens the end of the palate is a little reflected upward.
XI.
| Case. | Comp. | Series. | Specimen. |
| J | c1 | 9 | 1 |
Ornithocheirus dentatus (Seeley).
A fragment of premaxillary bone two inches long, fractured behind the socket for the seventh tooth. It most nearly resembles O. Sedgwicki and O. Cuvieri. Behind the second tooth the palate is 1/2 an inch wide; behind the sixth socket it is 5/8ths of an inch wide; the distance between these points is nearly 11/2 inch. The palate is flattened, with a sharp slight mesial keel and a wide concave channel on each side which dies away in front. The first pair of teeth are in front of the snout, rather small, and look forward. In this specimen the large third tooth is not developed on the left side. The second and third sockets are large and close together; the succeeding teeth are parted from each other by interspaces equal to their own diameter. They are gibbously elliptical. The sides of the jaw are gently convex from above downward; they round into each other to form a narrow rostral keel. Behind the second socket the jaw is 1/2 an inch high; behind the sixth it is nearly 7/8ths of an inch high.