No. V. — Temple of Jupiter Serapis. 273 



localities. The holes of these lithophagous mollusca have a 

 very peculiar form. They are pear-shaped, the external open- 

 ing being minute and gradually increasing downwards, the ani- 

 mal being found in the bottom. This proceeds from the in- 

 creasing size of the inhabitant as it grows older, which requires 

 it to employ the means furnished by nature for forming its 

 abode to correspond with the increasing magnitude of its shell. 

 The mytilus is therefore enclosed in a perpetual and solitary 

 prison, since no two animals can ever reside in the same hole. 



The perforations at the Temple of Serapis are of consider- 

 able depth and size, and therefore manifest a long-continued 

 abode of the Mytili, and consequently a long-continued im- 

 mersion in sea water. How this should have taken place 

 it is most perplexing to explain. The marks of the perfora- 

 tions begin at ten feet above the level of the pavement and 

 continue for six feet, exactly corresponding on all three 

 columns, as shown in the perspective view, Plate IV. With 

 regard to their present height above the sea, it is a singular 

 fact, that the platform of the temple is about one foot below* 

 high water-mark, (for there are small tides in the Bay of 

 Naples,) so that the sea water actually rises and falls at pre- 

 sent in the building, being only 100 feet from it. It cannot 

 possibly be imagined that the temple was built under such 

 circumstances. There are, therefore, proved to be two relative 

 changes of the level of the sea, which it is the business of the 

 naturalist to explain. By losing sight of the latter change al- 

 together, or by purposely giving it up as inexplicable, some 

 writers have given a novel and ingenious speculation, but ra- 

 ther, we think, overshot the mark. 



Two opinions at first were prevalent, and certainly they are 

 the most obvious and natural: That the sea had risen and 

 fallen successively as these marks indicate, supported by Fer- 

 ber and originally by Breislak ; or, as was most commonly 

 held, that the land was alternately lowered and elevated by 

 earthquakes, and hence the relative level of the sea changed, — 

 an idea entertained by the greater number of the older writers, 



* See Pini, Breislak, and Romanelli. That it is certainly below the 

 level of the sea my own observations confirm ; but some authors have made 

 strange mistakes on this subject. 



NEW SERIES. VOL. I. NO. II. OCT. 1829* S 



