1910.] Apternodu.^. M icroptcniodus, Necrolcstes. 259 



The type lower jaw of Apfvrnodus medla'vus, so far as known, ])resents 

 many resemblances to the jaw of Microgale dohsoni: r. g., ])eculiar shape of 

 angle, ridge on inner side of angle, sharp ridge above and in front of dental 

 foramen, position of condyle, molars with high pointed protoconid, very 

 small talonid, no hypoconid. The differences are mostly such as separate 

 more primitive from more advanced forms. In Apicrnudus the protoconids 

 are not so tall and not directed backward, the protoconid-paraconid shear is 

 less pronoimced, not so sharply turned forward, the metaconid is less re- 

 duccnl, the external cingulum is prominent, while in Microgale it is much 

 reduced. 



Mi era pie mod us (cf. Matthew, 1909, ])1. li) is also very likely a ])rimitive 

 member of the Centetidae. The talonid is less reduced than in Apiernodus 

 These two genera seem to throw but little light on the question whether the 

 small size of the talonid in Zalambdodonts is a primary or a secondary 

 character. 



THE NECROLESTIDM. 



The genus Necrolestes Ameghino from the Santa Cruz Beds (Lower 

 Miocene) is the Patagonlan anak)gue of the Cape Golden Moles. After a 

 very thorough examination of the dentition skull, vertebrne and limbs Pro- 

 fessor Scott (1903-5) showed that the resemblances between the tM'o genera 

 are very numerous and close and that "the differences are, for the most 

 part, such as usually occur between the earlier and later members of a phylum 

 or of two allied phyla It is not suggested that Necrolestes is to be re- 

 garded as the ancestor of any of the existing Chrijsochloridce, for it is itself 

 specialized in a diftVrent, though moderate way. What does seem probable 

 is that Necrolestes is an oft'shoot from some early members of the family 

 which was at the same time the ancestor of Chrysochloris" (op. cit., pp. 379- 

 380). Professor Scott also compared Necrolestes with Notoryetes and 

 showed that in every detail the former approximated to the Placental Insecti- 

 vore type, the latter to the Marsupial type, and that the resemblances be- 

 tween the two genera were entirely convergent. 



Necrolestes is less differentiated than Chrysochloris in the dentition, in the 

 retention of a faint postorbital constriction, stouter zygomata, more moderate 

 squamosal swelling on side of head, more normal carpals, etc. It has a long 

 bony rostrum which suggests the cartilaginous rostrum of the Shrew {cf. 

 Parker, 1885-6, pi. 31) and of the Centetidae. This bony rostrum may also 

 be represented among living forms by the prenasal ossicle of Soleiiodon. 

 Necrolestes is more specialized than Chrysochloris chiefly in the characters 

 of the femur. The series of seven cheek teeth (including the canine) de- 



