Marine Animals. 273 



demonstration which could give a more decisive support to the 

 theory of a solvent. 



On the other hand, it must be stated, that Mr Osier has 

 completely failed in his endeavours to detect this solvent. 

 Litmus paper applied to every part of the Saxicavae just taken 

 from their holes, shells stained, and sea water tinged with the 

 same test, in which animals of every size were kept till they 

 died, gave no indication of the presence of an acid. Even the 

 water in which a mass of rock containing above an hundred 

 Saxicavae had been kept for a week, afforded a precipitate, 

 when treated with oxalic acid, only equal to that obtained from 

 the same quantity of sea water. " Had the question been pre- 

 viously balanced," concludes Mr Osier, " our inability to de- 

 tect a solvent would justify strong doubts of its existence ; but 

 while all the facts connected with the natural history of the 

 Lithophagi afford a strong and consistent support to the theory 

 of a solvent, and are opposed as decidedly to the supposition of 

 penetration by a mechanical force, the failure of the experi- 

 ments cannot be considered to militate very strongly against 

 the only inference to be drawn from the facts." 



Here then the matter must for the present rest ; for though 

 Mr Osier has given strong reasons for supposing these animals 

 to possess the power of secreting a solvent capable of softening 

 the rocks in which they burrow, yet other naturalists, and 

 among them Poli, whose anatomical celebrity and talents for 

 observation are second to none, entertain a different opinion. 

 And as many of these Lithophagi burrow in wood as well as 

 in stone, and, as was remarked by Mr Stark, the same solvent 

 which was able to decompose calcareous stones might be very 

 ineffectual when acting on submerged wood, there still seem 

 doubts upon the subject, which future observation only can 

 resolve. 



Mr Osier's paper contains, besides, observations of much in- 

 terest on the Arenicola piscatorwn of Lamarck, (Lumbricus 

 marinus, Lin.) the Terebella conchilega, and some other ani- 

 mals which perforate the sand, the whole detail of which is 

 highly curious. The Arenicola piscatorum exudes a viscid 

 fluid from its anterior portion to which the sand adheres, and 

 forms a kind of tube ; and the Terebella conchilega forms a 



VOL. VI. NO. II. APRIL 1827- S 



