PREJUDICES OF SENSE. 161 



anatomical structure ; and we are at last compelled 

 to believe that the fact before us, although true, is 

 contrary to the usual course of nature. 



(100.) Prejudices of sense show themselves in va- 

 rious ways. A recent author, who writes upon shells, 

 finding a new genus of barnacle, occupying the de- 

 serted holes of some perforating bivalve*, concludes 

 that the excavations have been made by the barnacle, 

 and therefore names it Litlwtrya ! There is nothing 

 surprising or reprehensible in this, for it is an error 

 which all who trust alone to their eyesight would 

 most assuredly have fallen into. On looking further 

 into the matter, however, and ascertaining the gene- 

 ral structure of this group of animals, so admirably 

 illustrated by Polif, we see the physical impossi- 

 bility of their possessing this perforating power; 

 and it is known, moreover, that barnacles, instead of 

 being shell-fish, are articulated Annuloses, and belong 

 to the class of Insects. J The origin of the genus 

 Gionea has recently been quoted by one of the most 

 eminent mathematicians of the age§, as an example 

 of fraudulent Jwaxing ; although, I confess, it ap- 

 pears to me more allied to the subject now touched 

 upon. M. Gioeni finds, upon the coasts of Sicily, 

 the hard internal parts of a shell-fish (Sulla 

 lignarea L.); and this object, more resembling a 

 bivalve than any thing else, he mistakes for the 

 shell itself, and publishes it as such. The cele- 



* Cuvier, Reg. Animal, 2d ed. vol. iii. p. 177. 

 + Testacea? Utrinque Siciliae, vol. i. pi. 4, 5, 6. 

 \ See also Thompson's Zool. Researches, No. 3. 

 § Babbage on the Decline of Science, p. 175. 

 M 



