ro^ Arthrodires 



Smith Woodward, 1892. — "It seems to possess an impaired 

 nose, lip cartilages in place of functional jaws, and no paired 

 limbs ; thus agreeing precisely with the lampreys and hagfishes, 

 of which the fossil representatives have long been sought. It 

 is extremely probable, therefore, that Palaospondylus belongs 

 to this interesting category." 



Dawson, 1893. — PalcEOSpondylas suggests " the smaller snake- 

 like Batrachians of the Carboniferous and Permian; and I 

 should not be surprised if it should come to be regarded as 

 either a forerunner of the Batrachians or as a primitive tad- 

 pole." 



Gill, 1896. — "The group to which Palooospondyliis belongs 

 may be defined as Monorrhines with a continuous (') cranium, 

 a median nasal (?) ring, and a segmented vertebral column " 

 ' ' The cranium and segmented vertebral column indicate a 

 more advanced stage of development of the vertebrate line 

 than that from which the living ilarsipobranchs must have 

 originated. We may, therefore, with propriety isolate it as 

 the representative not only of a peculiar family {Palcrospondy- 

 lida-), but of an order or even subclass (Cyclicc) of vertebrates 

 which may provisionally (and only provisionally) be retained 

 in the class of Marsipobranchs." 



Dean, 1896. — "Place it with the Ostracoderms among the 

 curiously specialized offshoots of the early Chordates, but this 

 position would be at the best rmsatisfactory." 



Dean, 1898. — " Palccospondylus should not be given a place — 

 even a provisional one — among the Marsipobranchs." To be 

 accepted "as the representative of the new subclass (or class) 

 Cycliae constituted for it by Professor Gill." 



Parker & Haswell, 1897. — "There is some reason to regard 

 that Palcrospondylns is referable to the Cyclostomes." "A 

 distinctly higher type than recent forms." 



Gegenbaur, 1898. — " Discovery of Palccospondylus one of 

 the highest importance. If this organism stands in no way 

 near the Cyclostomes, the tentacles lose their higher importance, 

 since they also occur in other groups." "Through Palccospon- 

 dylus came also the attempt (Pollard) to deduce the presence 

 of the tentacular condition in the higher forms." {AIcni.~ln this 

 Gegenbaur has not consulted the literature accurately. At 



