68 REPORT—1862. 
On a New Species of Plesiosaurus from the Lias near Whitby, Yorkshire. 
By Dr, A. Carts, F.L.S., and W. H. Batty, F.G.S. 
The very large and perfect Plestosawus, the description of which formed the 
subject of this communication, was discovered in the Lias at the Kettleness Alum- 
its, near Whitby, on the 27th of July, 1848, and presented by the Marquis of 
Nstuinkby to the late eminent Surgeon, Sir Philip Crampton, as a mark of regard 
for his scientific attainments, who, in accordance with the anxious desire he always 
felt for the advancement of science, bequeathed it to the Royal Zoological Society 
of Dublin, in whose Gardens it was first exhibited to the public in May 1853; that 
Society, with the same object in view, has now deposited it in the Museum of the 
Royal Dublin Society, where every facility is offered for the study of this magni- 
ficent and largest example of-the genus known. The total leneth of this skeleton 
(of which a drawing of the natural size was exhibited), measured in the line of 
its vertebree, is 22 ft. 5 in. It lies in very nearly a natural position, resting upon 
the ventral surface, with the head and neck slightly inclined towards the right side ; 
the head, with the under jaw, is in a good state of preservation, and, being freed 
from the surrounding matrix, the principal bones composing it may be easily re- 
cognized ; the vertebral column has throughout its entire length fallen over towards 
the right side, presenting a slight irregular curve ; it exposes in the cervical series 
a side view of the centra or bodies of the vertebree, with their large neural spines 
(neurapophyses), and in some instances remains of the cervical ribs or hatchet- 
shaped bones (plewapophyses), the bodies of the dorsal vertebrae being almost 
entirely concealed, the massive ends of the neural spines and transverse processes 
projecting prominently above the general surface. ‘lhe caudal portion of the ver- 
tebral column is somewhat dislocated and thrown out of position, especially near 
its junction with the sacrum; the bodies are, however, in some cases well exposed, 
with their spines and processes. The ribs, thirty in number, are spread out on 
either side of the dorsal vertebrze, those of the left side being almost in their 
natural position. The anterior paddles are extended from both sides, on a plane 
nearly at right angles with the head and neck, the right posterior paddle stretching 
out in a direction parallel to the anterior, that on the left side inclining more to- 
wards the tail; in this paddle the tarsal bones, with their phalanges, are deficient, 
that portion haying been unfortunately carried to the calcining-heap before it was 
observed. 
The following are some of the principal measurements of this species, which it 
was proposed to call Plesiosawus Cramptont. 
ft. in. 
Total length of skeleton. ............04. COOLER: Thc i acgld 
Length of the skull from the point of the premaxillaries to 211 
thie pariotalierestiyy 34. FFL tals PF Lae NS Oe ae Leap 
Length of the lower jaw, from the symphyses to the extremity 3 10 
of the angular piece. ............... Sees Aa goo aye che 
Breadth of lower jaw across the tympanic condyles. ......... 2, oes 
Breadth of skull across the orbits ..............eceeceeees of ee ee 
Breadth of skull across the snout ..............cccceeeueee ORG 
Height of skull at posterior end, from angular piece of lower bat 
jaw to‘parietaltcrest 2. 22.52 eens On elon eel ets 
Height at extreme point of snout ............. ccs cec esse eee 0 6 
Length of cervical portion of vertebree, twenty-seven in number 6 0 
Length of dorsal and lumbar, thirty in number ........... ele 
Length of caudal, about thirty-four (some of the terminal ver- 5 6 
tebree being deficient) "40. SPATE RS, ypottaaieet 
(Total number of vertebree which can be counted ninety-one, 
Length of huieriy 200 SU ae ae eee Eien sabia! Snes’. 
Breadth of humerus at radial extremity ..................+. 010 
Leng th ‘oferatlins ay Hainer ule Ped Buy Pee Bry peice oe, 
Breadth of radius at proximal extremity .........cceeceeeeee 0 6 
Hiengthiofelnar eee, av Heyes 4 ey. Pad ea Ba ik Deed cones ieee 
Breadth of ulna at proximal extremity. ..,..escsceseeerreeee O 42 
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