1892.] POSITION OF NOTORYCTES TYPHLOPS. 369 



his own suggestion as to the incisor nature of the so-called canines 

 were correct, the creature would of course be an aberrant Poljpro- 

 todont ; but this absence of true canines would not affect its 

 Marsupial affinities, and would not in any way bring it nearer to the 

 Monotremata, because we know several genera of true Marsupials 

 which have no canine teeth. I have shown that Notary ctes is 

 aberrantly polyprotodont in spite of the presence of canine teeth. 



The enumeration of the following characters of Notoryctes will 

 perhaps help to settle its affinities: — 



A. Characters which prove Notoryctes to be a member of the 



Metatheria. 



1. Possession of an apparently permanent marsupiura, with two 



localized mammae and nipples. 



2. Well-developed inner angular process of the mandible. 



B. Characters of Notoryctes which occur also in some Metatheria. 



1. Large movable chevron- bones in the caudal vertebrae: Ma- 



cropus, Dasyurus, &c. 



2. Acromion much elongated and curved over the humerus : 



Dasyurus. 



3. Large osseous bulla auris : Peragalea (Macrotis) lagotis, 



Perameles, Dasyurus ursinus, PhascologaU. 



4. Very rudimentary marsupial bones : Thylacinus. 



5. Opening of marsupium directed backwards : Perameles. 



6. Presence of a prehallux, «'. e. the " sesamoid " bone attached 



by ligament to the entocuneiform, described by Stirling, 

 p. 180, pi. viii. fig. 8 s. Occurs also in Didelphys. 



7. Presence of an osseous patella: Perameles. 



8. Clavicles not directly attached to sternum, but by inter- 



vention of ligaments. A precoracoid unossified segment is 

 usually present in Metatheria. 



9. Presence of a " meso-scapular segment." Usual in 



Metatheria. 



C. Characters of Notoryctes, not found in recent Marsupials : see 



numbers 1, 2, 4, 6, 7, 8 of Edentate resemblances (p. 362) ; 

 further, in opposition to Monotremata, the prepenial, extrapelvic, 

 not abdominal position of the testicles combined with the absence 

 of a scrotum. Lastly, 3 incisors. 



D. Character unique in Notoryctes : fusion of the cuboid with the 



ectocuneiform of the foot. 



It so happens that the characters enumerated above do not permit 

 any decided conclusion, except that Notoryctes might be looked 

 upon as a " very old and generalized form " which has some charac- 

 ters in common with almost every other existing Marsupial family. 

 But this not unfrequent mode of cutting the knot of the difficulty 

 of settling the systematic position of a peculiar nature will hardly 

 be advisable in the face of the highly specialized structure of Noto- 

 ryctes. 



We have to make further inquiries. Notoryctes is fossorial to an 



