MAY, 1921. AMERICAN MARSUPIAL, C^NOLESTES OSGOOD. 103 



Frontals. The frontals are nearly as wide anteriorly as posteriorly. 

 They are smoothly rounded at the orbital border and have neither ridges 

 nor post-orbital processes, thus differing from most polyprotodonts. 

 There is no post-orbital process in Phascologale and some allied forms but 

 in these the frontals are more flattened and the orbital border is more 

 angular. Within the orbit, the frontals of Ccenolestes are less deflected 

 toward the midventral line than in other marsupials and thus provide 

 for the unusual space required by the large olfactory lobes of the brain. 

 A distinct venous foramen perforates the orbital border in its upper 

 anterior part. 



Lacrymals. The lacrymal is of moderate size and not largely 

 extended beyond the orbit. It is slightly gibbous but not ridged between 

 its facial and orbital parts. It is well separated from the nasals by the 

 frontal process of the maxillary. The lacrymal canal has a single open- 

 ing, thus differing from the didelphids and many other marsupials. It 

 opens on the orbital border, not within the orbit, but not so definitely 

 outside it as in other forms. 1 



Parietals. The parietals are broad and smooth with no suggestion 

 of a sagittal ridge. The suture between the two parietals and that 

 between them and the supraoccipital is practically obliterated in adults 

 although easily visible in most other marsupials except the peramelids. 

 Apparently the parietals reach laterally to the vicinity of the lambdoid 

 ridge as in other forms and are not shortened as in the figure published 

 by Miss Dederer (1909). A minute postparietal foramen is usually 

 present. 



Zygomata. The anterior root of the zygoma, as previously stated, 

 rises at the level of the third molar in marked contrast to the position 

 general among diprotodonts. The jugal is sharply narrowed anteriorly 

 and comes to a point just below the lacrymal canal. The arch has a 

 general sweep somewhat as in Phascologale and the bone is similarly 

 flattened but the anterior base is narrower and there is no trace of a 

 postorbital process, this last character being a resemblance to Perameles. 

 The jugal reaches the glenoid fossa as usual and its ending is truncate to 

 form a slight anterior boundary for the fossa, thus agreeing more nearly 

 with polyprotodonts than diprotodonts. The posterior root of the 

 zygoma is not inflated as in most diprotodonts, but it is more slender 

 than in dasyurids and didelphids and more nearly resembles the condi- 

 tion in the peramelids. 



Squamosal. The cranial part of the squamosal is not peculiar, being 



1 In Gregory's exhaustive comparative study of the lacrymal (Bull. Am. Mus. Nat. 

 Hist., XLII, p. 235, 1920), made since the above was written, it is concluded that 

 "The evidence of the lacrymal region is in harmony with the view that the caenoles- 

 toids are allied with the Peramelidae." 



