32 ANOMIID^. 



similarly sculptured. No less than thirty-four species 

 have been made out of the one now described ; and 

 naturalists of every country have had a hand in this 

 wholesale manufacture. Eighteen of these species have 

 been enumerated as synonyms by Forbes and Hanley. 

 The variability of the shell, however, is now such an 

 established fact, that a conchologist who would attempt 

 to restore any of these so-called species must have 

 greater ingenuity than even the learned knight, of 

 whom it was said 



" He could distinguish and divide 

 A hair, 'twixt south and south-west side." 



The variety " squamula" is flatter and smoother than 

 usual; " aculeata" has the imbricated scales pinched 

 up into vaulted or hollow spines ; and the narrow form 

 of " cylindrica " arises from the young Anomia selecting 

 for its resting-place a small stem of sea-weed, which 

 obliges it to assume a saddle-shape, not having any 

 room for lateral development. Occasionally specimens 

 are found exhibiting the characters of more than one 

 variety, being half " squamula " and half ' ' aculeata" 

 The animal is said to be poisonous ; and Mr. M c Andrew 

 informs me that the captain and some of the crew of his 

 yacht were suddenly taken ill at Vigo, after having eaten 

 some fine Anomia, which looked to them so temptingly 

 like oysters. The muscle of attachment appears to 

 have an excavating or eroding power, like the foot of a 

 limpet or other boring mollusk. When an Anomia is 

 fixed to the shell of an oyster, the lower part of the plug 

 is sunk below the level of the surface, and is separated 

 from it by a kind of sloping ditch. This gives a stronger 

 hold ; and the base of the plug is often spread out, so as 

 to increase the fulcrum. The structure of the plug is 

 very remarkable. It is composed of perpendicular 



