Professor Huxley makes the second and third phalanges 7-3/4 inches long, and the first only about 3/8 inch shorter, while the fourth phalange is 6-1/2 inches. These measurements are based upon some specimens in the Oxford University Museum. There is only one first phalange which has a length of 7-3/4 inches. The others are between 5 and 6 inches, or but little exceed 4 inches; so that as all the fourth phalanges which are known have a length of 6-1/2 inches, it is possible that the normal length of the first phalange in the larger species was 5-1/2 inches. The largest of the phalanges which may be classed as second or third is 8-1/2 inches, and that, I suppose, may have been associated with the 7-3/4 inches first phalange. But the other bones which could have had this position all measure 5-1/2 and 7-3/4 inches. The three species indicated by finger bones may have had the measurements:-- Phalanges of the wing finger ________________/\________________ | | I. II. III. IV. 7-3/4 8-1/2 [7?] 6-1/2 } length of each bone 5-1/2 7-3/4 5-1/2 [4-1/2?] } in inches. 4-1/2 ---- ---- ---- } The femur is represented by many examples--one 3-3/4 inches long, and others less than 3 inches long (2-9/10). In Campylognathus, which has so much in common with the jaw and the wing bones in size, the upper leg bone is 2-8/10 inches. Therefore if we assign the larger femur to the larger wing, the femur will be relatively longer in all species of Rhamphocephalus than in Campylognathus. Only one example of a tibia is preserved. It is 3-1/2 inches long, or only 1/10 inch shorter than the bone in Campylognathus, which has the femur 2-8/10 inches, so that I refer the tibia of Rhamphocephalus to the species which has the intermediate length of wing. These coincidences with Campylognathus establish a close affinity, and may raise the question whether the Upper Lias species may not be included in the Stonesfield Slate genus Rhamphocephalus. The late Professor Phillips, in his _Geology of Oxford_, attempted a restoration of the Stonesfield Ornithosaur, and produced a picturesque effect (p. 164); but no restoration is possible without such attention to the proportions of the bones as we have indicated. OXFORD CLAY A few bones of flying reptiles have been found in the Lower Oxford Clay near Peterborough, and others in the Upper Oxford Clay at St. Ives, in Huntingdonshire. A single tail vertebra from the Middle Oxford Clay, near Oxford, long since came under my own notice, and shows that these animals belong to a long-tailed type like Campylognathus. The cervical vertebræ are remarkable for being scarcely longer than the dorsal vertebræ; and the dorsal are at least half as long again as is usual, having rather the proportion of bones in the back of a crocodile. LITHOGRAPHIC SLATE