650 



HERBIVOROUS MARSUPIALS 



group of an insectivorous and very probably marsupial family. The 

 character of the calvarium of Triconodon offers nothing adverse to the 

 above views."'" 



Besides the mammalia above alluded to, belouging to 9 or 10 species 

 and to 5 or 6 genera, all of them insectivorous or predaceous, we are 

 indebted to Mr. Beckles for having disentombed (January 31, 1857,) the 

 remains of another genus exceedingly unlike the rest, the relations of 



I „'. 1. 



Flagiaulax BecklesU, Falc. 

 These two figures represent the same right ramus of the lower jaw seen on the opposite sur- 

 faces of a split stone, the two taken together affording data for a complete restoration of the jaw. 



Ul^per figure {outer side). 

 a, b, e'. Eight ramus of lower jaw magnified two diameters, a, 7>, outer side. &, o', d\ e', im- 

 pression of inner side. 

 a. Incisor. 



7>, c. Line of vertical fracture behind the pre-molars. 

 d'. Impression of the condyle in the matrix. 

 e'. Impression of top of coronoid process. 



/. Section of the anterior piece of the jaw at the fracture &. c, — a*, inner surface ; y, outer. 

 The notch at the top is formed by one of the sockets of the double-fanged true molar. 

 g. Section of the liinder piece near h, c; a?, inner; -?/» outer surface. 

 o'. Broken off inflected fold of inner margin buried in the matrix. 

 in. Sockets of tM'o molars. 



2), VI. Three pre-moiars, the third and last divided by a crack. 

 Lower figxire {inner side). 

 a\ d. Same lower jaw on the opposite slab of stone; &, (Z, e, inner side; &, a', h, cast and im- 

 pression of outer side. 

 a'. Outline of the incisor restored. 

 5, e. Line of vertical fracture, 

 vb. Condyle. 

 e. Coronoid. 



7i. Impression on the matrix of the three pre-molars. 

 i. Empty sockets of the two true molars. 

 n. Orifice f)f dentary canal. 



o. Indication of the raised and inilected fold of the posterior inner margin. 

 k. Third or largest pre-molar, magnified o^ diameters, showing the 7 diagonal grooves. 

 /. Corresponding pre-molar in the recent Australian Ilypsiprymnus Gaimardi, showing the 

 7 vertical grooves, magnified 8i diameters. 



''•• Allusion is here made to the crown of the skull before mentioned as occur- 

 ring in the same slab. In the text, at p. 295, I have cited the opinion given 

 by Professor Owen in 1854 (see Geol. Quai-t. Journ., vol. x. p. 431), that the 

 Spalacotherium was " more nearly allied to the placental than to the marsupial 

 insectivora," an opinion which, as will be seen, he is now disposed to modify. 



