ORDINAL TYPES OF MOLARS: INSECTIVORA 123 



the three external styles, parastyle, mesostyle, and metastyle, arc 

 strongly developed, as in the molars of Paiitolamlda (Fig. 140). 



A very interesting fact is that the molar dentition of tin- 

 ('entetidie has in one case followed the same line of carnassial 



^-ftas 



'W : 7 /\^fa" 



Tne -' 



FIG. 75. Tritubercular and carnassial upper molars in a Yiverrid and two Insectivores. A. 

 Ettplcres gouiloti. Crown view, ;/<l. x:*.. B. C'.nti.tcs ti:u tulutiis. Crown view, /!. x i. 

 C. Hcmicentcti'S madayascariensis, rn-. x J-. Note the long sectorial modification of the metastyle, 

 correlated with the blade-like character of the lower molars. In A and B, / probably represents 

 the fused para + metacone, the proto and hypocones being represented by the small basal cingular 

 outgrowths in B. All from Forsyth Major (op. cit. p. 23), but relettered. (Cf. Figs. (58, I'i'.i, i',:'./.) 



specialization as in Oxycena (Fig. 92), and Patriqfelis among the 

 Creodonta, the upper and lower sectorials becoming highly shear-like 

 (Figs. 74, 75)* 



Discussion of the G-idley- Woodward, Interpretation. 



The following interpretation of Gidley supports that of Woodward, 

 which is presented on pp. 208-213 (see also pp. 226, 227): 



' Woodward l found that in Centetes and Ericulus the main internal 

 cusp, usually termed the protocone, was first to develop, but he believed 

 this cusp to be the paracone, the whole tooth representing only 

 the antero-external triangle of such a form as Talpa, the protocone 

 and metacone not having been developed. This, as stated by Wood- 

 ward, is a modification of Mivart's view published in 1868," in which 

 he states his belief that in Centetes, Chrysocldoris 3 and like forms, the 

 main portion of the crown represents the union of the two external 

 prisms of Talpa and like forms. According to Mivart, the main 

 internal cusp of Centetes, Ericulus, Chrysochloris, etc. [Fig. 62 a, Nos. 3, 

 4, 6], was derived by the fusion of the paracone and metacone, 

 while the protocone and hypocone are wanting or rapidly diminishing 

 in size and importance. According to both Woodward and Mivart, 



* [In Erinaceus also, p 4 is a generalized sectorial with depressed antero-internal cusp 

 and oblique shear, and ni L similarly has an enlarged oblique protoconid-paraconid shear 

 and reduced heel. ED.] 



1 Proc. Zool. Soc. London, 1896, 588-589. 



-Journ. Anatomy and Physiol., Vol. II., 139, 1868. 



a " The form figured by Mivart has since been removed to a distinct genus, Bematisc.us, 

 Cope, Am. Nat., XXVI., 1892, 127. The typical Chrysochloris upper molar has 110 trace 

 of a protocone." 



