BUFFALO SOCIETY OF NATURAL SCIENCES 35 



At a first glance these mandibles look rather peculiar, and 

 Eastman (Bull. Museum Compar. Zool., xxxi, 31) thought that "their 

 afl&nities are probably with Dinichthys minor.'' This was before the 

 mandible of the latter had been described. But as was shown by 

 Hussakof ,^^ the minor mandible is markedly different from that of 

 Dinichthys, so much in fact, that it represents a distinct genus, 

 which he named Brachygnathus (subsequently renamed Hussakofia 



Fig. 6. Dinichthys intermedium ? Newberry. Pair of Mandibles. X |. 



E2033 



by M. Cossman).^* The present mandibles are not of this type but 

 undoubtedly belong to Dinichthys. 



If we compare the mandibles in detail with those of various species 

 of Dinichthys, we find that they agree fairly weU in proportions with 

 those of D. intermedius Newberry, and perhaps represent an immature 



I'Hussakof, L.: The systematic relationships of certain American Arthrodires. Bull. Am. 

 Mus. Nat. Hist., xxvi, 263-272, with pi. xlv. 1909. 

 " Cossman, M., in Rev. Critique de Paleo, 1910, p. 74. 



