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JAMES ERNEST KINDRED 



dibula is not nearly as great as it is in Gasterosteus or Salmo. 

 Although the whole ventral portion has swung anteriorly, the 

 foramen for the passage of the ramus hyomandibularis facialis 

 lies as before near the anterior margin of the dorsal head of the 



i-br. 

 III-IV 



Fig. 14 Ventral view of hyoid and branchial arches, 12-mm. Syngnathus. 

 Drawing made from wax model 150 times actual size. Ratio of drawing to model, 

 2:3. 



ABBREVIATIONS 



basi-br. III-IV, basibranchial cartil- 

 ages III and IV 

 br.I~V, branchial arches I to V 

 c.c, copula communis 

 cl.h., ceratohyal cartilage 



hyom., hyomandibula 

 hyp.h., hypohyal cartilage 

 ph.br., pharyngobranchial cartilage 

 styl.h., stylohyal cartilage 



hyomandibula. As in the 8-mm. stage, the dorsal portion is 

 relatively thinner than the ventral. 



The mesioventral surface of the hyomandibula is flattened 

 for articulation with the interpolated stylohyal, the plane of 

 articulation having been carried anteriorly by the shift in the 

 axis of the hyomandibula (figs. 10, 14). The shift which has 

 taken place in the hyomandibula is due to the part played by 

 the latter in changing the size of the oral cavity in the process 



