192 NATURAL SCIENCE [September 
Newton’s figures of the skull of the allied genus Scaphognathus 
(Phil. Trans. 1888, B. pl. 77 and 78). There appears to be 
no palaeontological evidence to warrant the great length which 
Owen gave to the hindermost ribs in his restoration, and these 
have, therefore, been considerably shortened, so that the contour 
of the ventral abdominal wall now passes evenly from the ribs 
to the ischial bones of the pelvis. So little is yet known con- 
cerning the coracoids and sternum of Ornithosauria that, beyond 
representing the sternum as keeled and as articulating with the 
first few ribs, but little has here been attempted. 
Of the four restorations which form the subject of the present 
article the greatest interest probably centres around that of 
Ichthyosaurus, inasmuch as the recent additions to our knowledge 
of this genus have rendered possible a very complete restoration. 
The species chosen is Jehthyosaurus communis from the Lower Lias 
of Lyme Regis, and the specimens which form the basis of the 
reconstruction are those in the Geological Gallery bearing the 
register numbers (41849) and (2000,1*). This is the same 
species as that of the well-known restoration of Owen’s (“ Anat. of 
Vert.,” vol. i, 1866, p. 170). An illustrated summary of recent 
papers on the Ichthyopterygia has already appeared in the pages of 
this journal (Lydekker, Wat. Sci., vol. i., 1892, pp. 514-521), and 
in this article is reproduced Fraas’s figure of the wonderfully well- 
preserved specimen of Ichthyosawrus quadriscissus, showing the 
complete outline of the body and affording incontrovertible evidence 
of the presence of a bilobed tail with the vertebral column running 
down the ventral lobe, and the existence of a series of irregular 
integumentary fins along the back (Fraas, Veues Jahrb. f. Mineral., 
1892, Bd. 2, pp. 87-90). These details are reproduced in the 
present restoration (Fig. 2), and, while the proportionate size and 
the details of the paddle skeleton are taken from the specimens of 
Ichthyosaurus communis above specified, the postaxial flap of the 
paddle, not supported by skeletal parts, is added from Fraas’s figure, 
from the museum specimen of Jcehthyosaurus intermedius (R. 1664), 
described and figured by Lydekker (Geol. Mag., dec. 3, vol. vi.,"1889, 
pp. 388-390), and from Owen’s figure of the paddle of Jehthyosaurus 
communis (2) (“ Liassic Reptilia,” part iii, 1881, pl. 28, fig. 5). The 
outline and details of the skull were introduced mainly from speci- 
mens (39492) and (R. 1164Pof Ichthyosaurus communis, both of 
which exhibit a very complete side view of the skull. In none of 
the specimens of IJchthyosaurus communis at the Natural History 
Museum are the bones of the pectoral girdle undisturbed, so that in 
restoring this part of the skeleton the shapes of the constituent 
bones were taken from specimen (41848), but their mutual relations 
from the very complete girdle which the museum possesses of 
