KNOWLEDGE 



[November 1, 1889. 



saurians ; of which the whole organisation is better known 

 than that of most of the other reptiles of the same epochs. 

 In the woodcut (Fig. 1) we give a copy of Sir Eichard 

 Owen's restoration of the entire skeleton, together with a 

 conjectural outline of the contour of the body when clothed 

 with flesh and skin. It will be seen from this that the 

 contour of the entire animal was of a whale-like type ; 

 there being no distinct neck, the body gi-adually passing 

 into the tail, and the two pairs of limbs formmg paddles 

 or flippers, adapted, like those of a turtle, for propelling 

 the body through the water, and perhaps also permitting 

 their owner to crawl awkwardly on the sea-shore in the 

 same mamier as the turtle does. From the circumstance 

 that m the skeletons from the Lias the tail is nearly always 

 broken at some distance from its extremity, it has been 

 suggested that the tail was furnished with a terminal fin, 

 after the fashion of the " flukes " of the Whales. In some 

 instances the fine-grained Lias mud has preserved traces of 

 the outer surface of the sldn of the Fish-Lizards, and we 

 learn from this, and also from the absence of any traces of 

 bony plates like those found in the skin of crocodiles, that 

 the skin of these saurians was quite naked ; and we are 

 thus shown another feature in which they resemble whales. 

 Moreover, in certain very rare instances, as is shown in the 

 beautiful example represented in Fig. 2. which has been 



Fiu. L'. — Part of one of the Fore Paddles of a Small Fish- 

 LizAKD FROM THE Ltas OF Baurowon-Soar. hu, boue of upper 

 arm ; r, ti, bones of fore-arm ; the other letters indicate the bones of 

 the wrist, below which are the bones of the fingers. 



recently presented by Mr. M. Browne, of the Leicester 

 Museum, to the National Collection, the contour of the 

 soft parts of the]paddles is accurately delineated in the stony 

 matrix. We thus see that the fleshy part of the paddle 

 formed but a comparatively narrow band in advance of the 

 bony framework on the front border of the fin (right side of 

 Figure) ; but on the opposite or hinder border (left side 

 of Figure) we find the soft parts forming a broad fin-like 

 expansion admirably adapted to obtain the full advantage 

 of the stroke of the limb in swimming. 



As we are on the subject of the paddles, we may take the 

 opportunity of noticing the very remarkable structure of 

 their bony framework, which is quite imlike that foimd in 

 any other animal, although e\-idently only a modification 

 of the same ground-plan. In most vertebrate animals, as 

 in man, the skeleton of the ai-m, or fore limb, presents the 

 following features : — The upper-arm has one long single 

 bone ; in the fore-arm there are two slender bones lying 



side by side and separated by an interval ; the wrist has 

 two rows of small cuboidal bones ; wliile the limb terminates 

 in five fingers, of which, with the exception of the thumb, 

 each has three long bones, which are respectively separated 

 from the wrist by a similar but somewhat longer l)one. 

 Turning to the fore paddle of the Fish-Lizard (Fig. 2), we 

 easily recognize in the topmost bone the single bone of the 

 upper arm, although this has become much shorter and 

 thicker than is usually the case. In the two short and 

 angulated bones, marked /■ and if, it is more difficult to 

 recognize the representatives of tlie long bones of the fore- 

 arm ; but that they really are such representatives is at 

 once shown by their position. Passing over the bones of 

 the wrist, we find that the bones corresponding to those of 

 the fingers, instead of being elongated and limited to three 

 in each of the five fingers, are polygonal in contour, and 

 arranged in as many as seven or eight longitudinal rows, 

 while those of each finger (as shown in Fig. 1) are exceed- 

 ingly numerous. The whole structure forms, in fact, a 

 complete bony pavement, which in the li\±Qg animal nuist 

 have been perfectly supple, and thus have formed one of 

 the most efficient and powerful swimmmg organs known in 

 the whole animal kingdom. The paddles of the whales 

 resemble those of the Fish-Lizard in the great number of 

 bones in each finger, but they differ m that the number 

 of the fingers themselves does not exceed the miiversal five. 



In the few words that we can devote to the skull of the 

 Fish-Lizard, we may observe that the muzzle was pro- 

 duced into a more or less elongated beak (Fig. 1), while 

 the nostrils were placed close to the eye, and the soft parts 

 of the latter were strengthened with a ring of bony plates 

 surrounding the iris and pupil, as is the case in birds. The 

 teeth were large and pointed, and implanted in a deep 

 groove m the jaws. Their pointed cro\\Tis at once tell us 

 that the Fish-Lizards were creatures of carnivorous habits, 

 which preyed on other inhabitants of the Secondary seas. 

 Curiously enough in the approximation of the nostrils to 

 the eyes, and also in their sharply-pointed teeth, the Fish- 

 Lizards present further resemblances to the Whales, 

 resemblances which we may probably explain by the 

 similar conditions of life of these two widely difterent 

 groups. 



Before leaving this brief notice of the anatomy of these 

 saurians, a few words must be said as to the structure of 

 the back-bone or vertebral column. It wiU be seen from 

 Fig. 1 that the whole of this column forms a continuous 



Fig. 3. — End and Side Views of the Body of One of the 

 Segments of the Back-rone of a Small Fish-Lizakd. 

 a, b, Surfaces for the attachment of the rib. 



series, tapering at the two extremities ; and the various 

 segments, or vertebra?, of the difterent regions of this 

 column are so alike that it requires some practice to 

 distinguish them. As is well known, each vertebral segment 

 in all the vertebrate animals consists of an arch enclosing 

 the spinal marrow, and of a sub -cylindrical body supporting 

 the arch and underlying the marrow. As a rule, the body 

 and the arch are more or less firmly imited together, but 



