A second English Pterodactyle is found in the Upper Lias of Whitby. It is only known from an imperfect skull, published in 1888. It has the great advantage of preserving the bones in their natural relations to each other, and with a length of head probably similar to Dimorphodon shows that the depth at the back of the eye was much less; and the skull wants the arched contour of face seen in Dimorphodon. The head has the same four lateral vacuities, but the nostril is relatively small and elongated, extending partly above the oval antorbital opening, which was larger. There is thus a difference of proportion, but it is precisely such as might result from the species having the skull flatter. The head is easily distinguished by the small nostril, which is smaller than the orbit of the eye. The animal is referred to another genus. The quadrate bones which give attachment to the lower jaw send a process inward to meet the bones of the palate, which differ somewhat from the usual condition. Two bony rods extend from the quadrate bones backward and upward to the sphenoid, and two more slender bones extend from the quadrate bones forward, and converge in a #V#-shape, to define the division between the openings of the nostrils on the palate. The #V#-shaped bone in front is called the vomer, while the hinder part is called pterygoid. The bones that extend backward to the sphenoid are not easily identified. This animal is one of the most interesting of Pterodactyles from the very reptilian character exhibited in the back of the head, which appears to be different from other specimens, which are more like a bird in that region. Yet underneath this reptilian aspect, with the bony bar at the side of the temporal region of the head formed by the squamosal and quadrate bones, defining the two temporal vacuities as in Reptiles, a mould is preserved of the cavity once occupied by the brain, showing the chief details of structure of that organ, and proving that in so far as it departs from the brain of a Bird it appears to resemble the brain of a Mammal, and is unlike the brain of a Reptile.