The Anatomy of Chlamydyselachus 



417 



Text-figure 75. 

 Median sagittal section (x 12) showing thyroid gland and thyroglossal 



duct of an adult Chlamydosdachus. 

 a., artery; c, basihyoid cartilage; d., thyroglossal duct; p.i., pharyngeal denticle; thyr., 



thyroid gland. 

 Drawn from Specimen No. I in the collection of the American Museum of Natural History. 



Text'figuer 76. 

 Median sagittal section (x 10) showing thyroid gland of an adult OnUmydoselachus in which 



there was no thyroglossal duct. 



a., artery; c, basihyoid cartilage; p. d., pharyngeal denticle; thyr., thyroid; d., vein. 

 Drawn from Specimen No. Ill in the collection of the American Museum of Natural History. 



