1897.] ON MAMMALS FEOM NORTH AtTSTEALIA. 31? 



he adds that " its diphy cereal (or perhaps heterocercal) condition " 

 is also common to many groups. Well, I have never seen a 

 " heterocercal " Palceospondylus in spite of the many specimens 

 with well-preserved tails which have come under my observation. 

 Nor have I, although I must have examined nearly two hundred 

 examples of the little creature in question, many of them in a 

 much better state of preservation than the one which is the special 

 subject of this paper, ever seen anything like the shadowy furrows 

 interpreted by Dr. Dean as pectoral fin-rays. 



Therefore I must, in conclusion, state my belief that the exami- 

 nation of this specimen leaves tlie question of the affinities of 

 PalcEOspondylus precisely where it was after I had written my last 

 paper on the subject. 



My warmest thanks are, however, due to Dr. Bashfoi'd Dean 

 for his kindness and generosity in sending his specimen again 

 across the Atlantic for re-examination by British palseichthyologists. 



2. On a Collection of Mammals from North and 

 North-west Australia. By R. Collett. 



[Eeceived February 10, 1897.] 

 (Plate XXTII.) 



Mr. Knut Dahl, a young naturalist, returned to Norway in 

 May 1896, after spending three years, from 1893 to 1896, in 

 South Africa and Australia for the pui'pose of collecting zoological 

 specimens for the University of Christiania. 



In June 1894 he ari-ived at Port Darwin, in North Australia, 

 and at once commenced his researches in the inner districts of 

 Arnhem Land. He subsequently visited Victoria River (south of 

 Arnhem Land), and finally remained at Roebuck Bay, North- 

 west Australia, from October 189-5 to February 1896, where he 

 likewise obtained interesting collections. He collected altogether 

 examples of 34 species of Mammals, 31. of which maj'^be identified. 

 Besides this, several others were observed without being procured. 

 Two of the species of which specimens were brought home I con- 

 sider new to science (PseudocJiirus daJilii and Sminthopsis mtelc(.),andL 

 several of the others are rare and seldom met with in collections. 



I shall therefore append a short account of the Mammals which 

 have been brought home and which are all preserved in the 

 Zoological Museum at Christiania, and add to it a short description 

 of the most important of the places visited, together with their 

 peculiarities, from the reports I have received of them from 

 Mr. Dahl. 



I owe my thanks to my friend Mr. Oldfield Thomas for having 

 assisted me in determining some of the more doubtful specimens. 



Characteristic of the whole of Arnhem Land is a mighty forest, 

 which more or less covers the entire country. 



Port Darwin, the first locality visited, is characterized by fiat, 



