N. ROSÉN, STUDIES ON THE PLECTOQNATHS. 



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Fig. B. — Spheroides teatudineua L. Diagrams of praecaudal vertebrse. I, 

 side view. IT, transverse section of a vertebra with spina bifida. 



Finally a few remarks shall be made on the stateraenta 

 of earlier writers.. Hollard described the vertebrae of the 

 Tetrodontids together with those of the Diodontids; but his 



