Oct., 1891. midland union of natural history societies. 223 
it clear that the structure is by no means primitive ; it is 
obviously modified and secondary, and this inference is con¬ 
firmed by the fact that in Triassic strata, in rocks, that is, 
which are older than those in which the fully developed 
Plesiosaurs are found, there occur the fossil remains of 
creatures which are in process of becoming Plesiosaurs. 
These animals have a little head placed on the end of a long- 
neck, just as in Plesiosaurus, and resemble them in other ways, 
but in the character of the limbs they are somewhat different. 
In one animal (Neusticosaurus) (Fig. 10) the fore-limbs are modi¬ 
fied as paddles, just as in Plesiosaurus; while the hind-limbs are 
like those of other reptiles, that is, each hind-limb is made up of 
five well-formed fingers, each enclosed in a finger-stall of skin, 
and each having a claw at the end. Neusticosaurus is half a 
Plesiosaur, we might say. Another animal ( Dactylosaurus ) 
(Fig.9) has the long neck and small head, but in it both the pairs 
of limbs have the usual reptilian characters. Dactylosaurus 
is, in fact, a lizard which is a quarter the way to being a Plesio¬ 
saur. It seems plain that the ancestors of the Plesiosaur 
were carnivorous lizards which took to living in the water. 
In adaptation to their mode of life, the neck became 
lengthened, while the bones of the limbs became flattened ; 
the fingers and toes became first webbed, then completely 
covered in with membrane, until at last the paddle of the 
Plesiosaurus was developed. 
(To be continued.j 
MIDLAND UNION OF NATURAL HISTORY SOCIETIES. 
FOURTEENTH ANNUAL MEETING- AT DUDLEY, 
On Tuesday and Wednesday, October 13th and 14th, 1891. 
President :— G. H. Claughton, Esq. 
Birmingham 
Dudley 
Hon. Secretaries : 
.. Lawson Tait, LL.D. M.D., F.R.C.S. 
/ W. Madeley. 
** 1 W. Wickham King. 
PROGRAMME OF PROCEEDINGS. 
Tuesday, 13th October. 
The members of the Council will assemble at the Dudley 
Institute at one p.m. 
The Annual Meeting 
will be held at 1 30, in the Committee Room, Dudley Institute. 
The report of the Council and the Treasurer’s accounts will 
