128 Reviews — A. 8. Woodward's Catalogue of Fossil Fishes. 



In the family OnychodontidEe is included the singular genus 

 Onycliodus, in which a scroll-like symphysial tooth-bearing element 

 is present, and concerning which it is much to be desired that further 

 details may soon be discovered. 



The Actinistia (Cope) include the single family of Coelacanthidge, 

 of which a concise account is given. Under Cladistia (Cope) we 

 have the recent family of Polypteridee, as yet unknown in a fossil 

 state. Certainly Polypterus differs in inany salient points from the 

 known fossil Crossopterygii, and, as Mr. Woodward remarks, "The 

 di- or tri-basal character of the pectoral fins in conjunction with 

 other features may perhaps justify the recognition of this group as a 

 distinct order." 



ACTINOPTERYGII. 



Under " Chondrostei " our author includes the Podopterygii of 

 Cope (Acipenseridee, Polyodontidge, Chondrosteidse), plus the Palffio- 

 niscidce, Platysomidfe, Catopteridee, and Belonorhynchidse. 



It is certainly satisfactory to myself that Mr. Woodward has 

 adopted the placing of the Palaeoniscidae and Platysomidae with the 

 Sturgeons, w^hich, since I proposed it in 1877,^ has hitherto for the 

 most part been either opposed or ignored. In his conception of 

 the group, however, he does not place much stress on the peculiar 

 heterocercy of the tail, but more on the excess in number of the 

 dermal rays of the median fins over that of their supporting 

 ossicles (baseosts), and hence he admits into it the seraihetero- 

 cercal Catopteridce, and the abbreviate-diphycercal Belonorhynchidce, 

 previously considered to belong rather to the Lepidostoid series. 

 Certainly the Palaeoniscus-like aspect of the dorsal and anal fins of 

 Catopterus is extreme. In the brief definition of the Polyodontidae, 

 p. 424, he gives as a character that the cranial shield has a " median 

 azygous series of bones," but I have already under Dipnoi pointed 

 out that there is no median plate at the back of the skull in 

 Polyodon, as in Acipenser, though further on, between the frontals, 

 thei'e commences a longitudinal series of four small ones extending 

 to the extremity of the paddle-like snout, and which doubtless 

 represent the single large median super-ethmoid of Palceoniscus. 



In treating of the Palasoniscidas the author gives a useful synopsis 

 of the genera comprised in this extensive family, which he describes 

 as "a provisional attempt to follow the lines of evolution." I quite 

 agree with him that the obliquity of the suspensorium is a mark of 

 specialization, and that such genera as Canobiiis and Euryle.pis are 

 in this respect more primitive than others such as Cheirolepis or 

 Pygopterus, in which it is extremely oblique. So likewise is the 

 tendency of the scales to pass from the rhombic to a circular and 

 deeply imbricated form, as in Cryphiolepis and Coccolepis ; in fact 

 the scales of the former genus become so nearly absolutely cycloidal 

 that when I first came upon them I referred them to Coelacanthus. 

 In a similar light is to be viewed the degeneracy of the squamation in 

 Phanerosteon, in which the scales over the greater part of the body 



1 " Carboniferous Fishes" (Men. Palseont. Soc). 



