CONCHOLOGY 



the hammer form to be still preserved in these, in the next species. 

 Malleus Normalis, instead of two lobes, the hammer head, if it may 

 be so expressed, has but a single lobe : in Malleus Anatinus there is 

 only one lobe, and that very small ; and in Malleus Vulsellatus, 

 although characterised as loho oblique p or recto ^"^ the appearance of 

 the shell implies rather the total absence of any lobe, for the lobe, if 

 so it may be termed, is so indefinite, that it cannot be referred with- 

 out violence to the genus Marteau, while we consider its hammer 

 like form as a leading character of the genus. With exception to 

 this inconstant character which may be qualified with the expression 

 ^* deformed and generally hammer shaped," we have no objection to 

 the Malleus genus, because the byssus of the animal by means of 

 which it can affix itself to other bodies, and the peculiar sinus or 

 sulcation of the hinge through which the byssus passes from the 

 animal to those extraneous bodies, are sufficient to remove it from 

 the Ostrea genus, in which case if we still adhere to the Linnasan 

 method we can place it only among his Mytili or Pinnae, and it has 

 certainly less affinity with either of those than with Ostrea. Perhaps 

 the name of Perna under which this shell has been mentioned a few 

 years ago might have been as well preserved, but that name Lamarck 

 assigns to an extensive genus of which Ostrea Isognomum is the 

 type, and it is therefore better to retain the name Malleus than to 

 alter it to another which could not fail at this time to create confu- 

 sion. The same consequence would as unquestionably result were 

 we to sub-divide the Malleacdes into different genera according to the 

 configuration of the shell or number of its lateral lobes. 



The definition of Malleus in the Rbgne Animal of Cuvier appears 

 to intimate the same objection ; it does not consider the hammer like 

 form of the shell as any criterion, it is only stated that the Marteaux 



