Mr. F. W. Hutton on Tursio metis. 357 



Eastern Hemisphere, while the Phyllostomidse are limited to 

 America, the Vespertilionida? and Emballonurida3, as directly 

 derived from the ancestral group (Palajochiroptera), being 

 common to both hemispheres. But another distributional fact 

 may also be observed — namely, that the most highly differen- 

 tiated and most highly organized species of the Vcspertilionine 

 and Emballonurine alliances respectively belong to families of 

 very limited distribution. Thus the closely allied Nycter'uhe and 

 Rhinolophidae have nearly the same distribution — the former 

 family being confined to tropical and subtropical Africa, Asia, 

 and Australia, the latter to the same continents, a few species 

 extending into Europe* while the Phyllostomidaj are absolutely 

 limited to tropical America. The Pteropidae, including the 

 largest bats, are strictly limited to the tropical and subtropical 

 regions of the Old World from Western Africa to the Navi- 

 gators' Islands ; and of these the genera containing the most 

 highly differentiated forms have also the most strictly defined 

 range. This is precisely what we should expect if we regard 

 these families as later developments of the Vespertilionidte and 

 of the Emballonuridre. While the older forms are found in 

 both hemispheres, the later developments are still limited 

 to the regions, or remains of the regions, in which they first 

 originated, restricted by changes which had taken place in the 

 distribution of land and water previous to their origin, but 

 subsequent to the appearance of the forms from Avhich they 

 were derived. 



XLVIII. — On the li Cow-fish" (Tursio metis) of the Sounds 

 on the West Coast of Otago, New Zealand. By F. W. 

 Hutton, Curator of the Otago Museum, Dunedin. 



Tursio metis, Gray, Zool. Erebus and Terror, 

 p. 38, t. xviii. 



Female. Teeth ^~Y2> exactly three in an inch. Body elongate, 

 thickest in front. Dorsal fin falcate, commencing before the 

 middle of the back ; its height less than the length of the 

 pectoral fins. Pectoral fins as long as the gape, falcate, on a 

 restricted base. Lower jaw longer; attenuated portion of the 

 snout short. 



Colour. Above and upper jaw dark slate-blue, passing gra- 

 dually into white below ; the white of the underparts not 



