464 SCIENCE PROGRESS 



arthrodires as an order of Dipneusti precludes their association 

 with ostracophores [Cephalaspis, etc.] in any sense." 



The third paper of the triad, and the last on the whole list, 

 is one on the classification of Selachian fishes communicated 

 by Mr. C. T. Regan, of the British Museum, to the Proceedings 

 of the Zoological Society (1906, pp. 722-58). It deals, of course, 

 with both recent and fossil forms ; and perhaps its title is a 

 little misleading, since the author includes in the Selachii 

 (= Elasmobranchii) not only the sharks and rays, but the 

 chimseras and their extinct relatives (Holocephali). It is this 

 marked departure from the classification adopted in the British 

 Museum Catalogue of Fossil Fishes which renders it necessary 

 to refer to the paper in the present article. Which of the two 

 views will ultimately prevail remains to be seen, although the 

 present writer has a very strong opinion of his own on the 

 subject. A startling suggestion in Mr. Regan's paper is one to 

 the effect that the "Selachii" will eventually have to be separated 

 from the class Pisces as typified by the Teleostomi. To this 

 the reply is, " Cui bono?" 



In conclusion, the writer must again crave the indulgence of 

 his readers for such imperfections as may exist in a record which 

 from the very nature of the case must be incomplete. 



Note Added 



As this proof was going to press an important memoir 

 (unfortunately in Danish) by Mr. Herluf Winge, on extinct and 

 living Ungulates of Lagoa Santa, Brazil, was received. It is 

 published in E. Mitseo Lundi Copenhagen, and deals not only 

 with the subject forming the title, but likewise with the classi- 

 fication of the Ungulata generally. 



