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NEW YORK STATE MUSEUM 



i c h t h y s major, have been found by Dr Traquair to belong to " a very 

 different creature from the Pterichthys (Bothriolepis) major 

 of the adjoining district of Elgin," and are determined by him as Astero- 

 lepis maxima. The same author further observes that "it is remark- 

 able that while Asterolepis maxima is unknown in those strata 

 round Elgin which are characterized by Bothriolepis major, not a 

 single remnant of any species of Bothriolepis has ever been found in the 

 Asterolepis-bearing beds at Nairn. Other fish remains are very rare in 

 these beds, but such as I have obtained leads me to suspect that we have 

 here to deal with quite a different fauna from that of the closely adjoining 

 district of Elgin." Accordingly, the identification of the two figured 

 specimens referred to should be amended so as to read "Asterolepis 

 maxima, from Nairn." 



Formation and locality. Elbert formation (Upper Devonic) ; Rock- 

 wood and Devon Point, Col. 



Class PISCES 

 Subclass ELASMOBRANCHII 



Order PLEUROPTERYQII 



The only known representative of this order, and at the same time, as 

 indicated by the condition of its paired fins and other features, the most 

 primitive type of Elasmobranch yet discovered, is the Upper Devonic 

 and Lower Carbonic genus Cladoselache. Amongst all fossil fishes this 

 genus is regarded as furnishing the most important testimony in favor of the 

 lateral fin fold hypothesis. In view of its extreme importance froin a mor- 

 phological and phylogenetic standpoint, it seems desirable to offer the follow- 

 ing account of its organization, compactly drawn up by Smith Woodward : 



The fish is elongated and round-bodied, with a short blunt snout and 

 forwardly placed eye. The precise characters of the cranium are unknown ; 

 but the olfactory capsules are large, placed close together, and terminal. 

 The mouth is also terminal, the upper and lower jaw being similar in shape 

 and size, and supported by a slender elongated hyomandibular. The teeth 

 are largest, longest, and most acutely pointed at the symphysis of the jaw, 

 smallest and shortest at the angle of the mouth. The transverse series 

 are closely apposed, and not separated as in the modern Chlamydoselachus ; 



