184 TEREDINID^. 



which were found by the late Professor Adams at 

 Jamaica. T. fimbriata is said by Dr. P. Carpenter to 

 be a native of ^^ancouver^s Isle. 



T. minima of De Blainville is common in the Mediter- 

 ranean, but has not been noticed on our shores. It has 

 rather long and large close-jointed pallets with plain 

 edges; the valves are very much smaller than those 

 of any British species, and somewhat resemble the 

 stunted form of T. navalis. The pallets of this species 

 and T. fimbriata may be taken for miniatnre ears of 

 barley with long stalks. T. minima is the T. bipalmata 

 and T. bipalmulata of Delle Cliiaje, T. palmulata of 

 Philippi, T. Philippii of Fischer, and T. serratus of 

 Deshayes's MS. 



Having disposed of the headless mollusks, which are 

 represented by the classes Brachiopoda and Conehifera, 

 we next proceed to consider such as have a head. These 

 exhibit a greater diversity of shape and a more compli- 

 cated structure ; their organs and functions are more 

 specialized. Thus creation moves, step by step, higher 

 and higher, until at length that mental pinnacle is 

 reached, which is attainable only by the chiefest among 

 our own kind. In the suggestive language of Tennyson, 



" All nature widens upward. Evermore 

 The simpler essence lower lies ; 

 More complex is more perfect, owning more 

 Discourse, more widely wise," 



The first in order among the Cephalic MoUusks is a 

 peculiar class, partaking somewhat of the nature of the 

 Acephala, and forming a link between the two. It is the 



