148 



he refers. It is certain that the indications of the mutilated parts of my original speci- 

 mens have not proved "illusory." 



But such indications were not the sole grounds of my conclusions ; I was also guided 

 by a principle. It is that laid down by Cuvier in the van of his immortal work of 

 Restoration of the oxtinct Mammals of the Paris Basin. 



The aberrations of some contemporary labourers in this field show that it will bear 

 repetition : — " La premiere chose a faire dans l'etude d un animal fossile est de recon- 

 noitre la forme dc ses dents molaires ; on determine par-la s'il est carnivore ou herbivore"*. 



These test-teeth were fortunately entire in the upper jaw of the skull of Thylacoleof, 

 and in the cast of the lower jaw originally described J. 



The major part of the molar series was represented by one large and most efficient 

 carnassial, followed by a single small tubercular above, which was opposed to a semi- 

 tubercular molar and a second more minute tubercular tooth below. 



Here was no molar machinery for the mastication of vegetable food, but a maximized 

 modification of the teeth for the division of fleshy fibre, and so much of the tubercular 

 form added for the final crush or squeeze of gristle or other tough part escaping the 

 shears, as exists in the most carnivorous of the placental mammals. 



Location of Laniaries. — From these facts, with faith in the Cuvierian principle, I 

 inferred a concomitancy of laniary teeth at the fore part of the jaw " to pierce, retain, and 

 kill"§ the prey, whether such laniaries held the relative position to a suture technically 

 determining them to be either " incisors " or " canines." It is now determined that these 

 laniaries are, as was inferred in the Second Section ||, incisors. A co-adapted pair at the 

 fore part of the lower jaw were opposed to a slightly separated pair in the upper jaw. 



To this demonstration applies the following objection against the inference as to 

 function : — 



" Throughout the Mammalia, where teeth perform the functions of canines to ' pierce, 

 retain, and kill,' they are held well apart through the interposition of a line of incisors — 

 the end being obvious : the points of penetration are doubled, the grasp is strengthened 

 by widening the base, and the dilacerating and killing powers are multiplied "^[. 



To this 1 reply that, were a pair of bayonets cemented side by side and the forces of 

 two brawny arms concentrated on the thrust, their perforating and lethal power would 

 be increased. I fail to see how such " collateral arrangement in the axis " of the piercing 

 force "would place them at a disadvantage to the end to be attained "**. 



Dr. Falconer admits that "a Rat when seized can inflict a smart wound on the hand"ff. 

 I can add experience of loss of young poultry showing by the wounds on their legs how 

 they had been brought down from the perch, and by wounds on the neck how they had 



* Recherches sur les Ossemens Fossiles, 4to, torn. iii. (1822) p. 1. 



t Philosophical Transactions, 1859, Plate xi. figs. 1 & 2. % Id. ib. fig. 3. 



§ Owen's ' Palaeontology,' 8vo, 1860, p. 320. 

 || See, also, Philosophical Transactions, 1866, p. 80. 

 if X. p. 352 ; XI. p. 435. ** Id. ib. ft Id. ib. 



