XYLOPHAGA. 19 



rage at least one-half is occupied by its burrows ; tlie Xylo- 

 phaga has never, like the Teredo, been observed by my cor- 

 respondent to form a testaceous tube or lining to its shell. 

 Many of the chambers of the Xylopliaga before me are one 

 inch and a half in length, thus exceeding by one-half the 

 longest noticed by Turton. The shells of my largest speci- 

 mens are 5i lines in length: the two valves joined at the 

 liinge occupy a space of 5 4 lines in diameter. This species 

 differs from Teredo navalis by boring against the grain of 

 the wood (all of which is pine) in a diagonal manner.'" 



The habit last alluded to may remind us of certain cross- 

 grained natures which, always boring their way against the 

 grain, delight in creating obstacles in order to overcome 

 them, and love a position of antagonism for the excitement 

 it produces. But how much better is it to work, if possi- 

 ble, like the Teredo, with the grain, and be the better pre- 

 pared to meet and overcome all difficulties. 



