380 CYPRINID^E. 



of union in the two parietal bones at the top ; a deficiency 

 which has been noticed by the late Rev. Lansdown Guilding 

 to occur in the Iguana tuber culata, or common Guana,* and 

 to which aperture that lamented naturalist applied the term 

 foramen Homianum, in honour of Sir Everard Home, ob- 

 serving that the opening did not afford a passage to any 

 nerve or blood-vessel. This peculiarity in the Loach, it will 

 be observed, is another instance of a relation in structure 

 between the fishes and reptiles, some of which have been 

 already adverted to at page 40. 



The vignette exhibits a magnified representation, four 

 times larger than the natural size. 



* Zoological Journal, vol. i. p. 130. 



