624 Subclass Dipneusti, or Lung-fishes 



(4) The Dipneusti probably originated from more specialized 



Crossopterygii, e.g.,' from the neighborhood of the 



Holoptychiidce. 

 (s) The Teleostei differ in so many respects from the Clioii- 



drostci that they should rank as an order, in which 



the Holostci are included. 



