PLATE 8 



EXPLANATION OF FIGURE 



21 Dissection of hyobranchial muscles of adult; dorsal view. The dorsal 

 surface of the tongue has been partially removed, and the posterior edge entirely 

 so, to show underlying structures. The lines 22 to 27 show approximately the 

 levels at which the sections shown in figures 22 to 27, respectively, were cut. 

 These levels cannot be shown exactly, as the position of the apparatus at the 

 time of fixation was different in the two specimens. X20. 



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