Dr. J. E. Gray on a Fossil Hydraspide. 339 



supported by one of the most popular writers on astronomy 

 and physics of the day ^j and the jury adopted this explanation. 



On the other side it was contended that the open circular 

 hole observed in the timber had been made for a tree-nail, 

 and had been left unclosed, and only covered by the copper- 

 sheathing of the vessel ; but I do not recollect that any evi- 

 dence was brought in support of this view, which I believe is 

 the true explanation ; for certainly, even allowing that the 

 SAvord-fish could withdraw its beak, the hole which the beak 

 had made would not have remained circular, but would have 

 become more or less filled up. 



May not the whole case be considered an illustration of the 

 want of practical and scientific instruction by what are called 

 the members of several of the most instructed professions ? 



The swordfish which is supposed to have attacked " the 

 good ship ' Dreadnought ' " must have been a very clever fellow, 

 much in advance of his brethren. With his conical bony 

 beak he succeeded in making a cylindrical hole about an inch 

 in diameter through the timbers of the ship, similar to that 

 made by an auger; and having twisted himself into it, he 

 managed, having done the mischief he desired in revenge for 

 having been caught by the ship's crew, to withdraw his beak 

 and to sail away uninjured. He did not do his swimming- 

 parallel to the surface of the water (as most fishes do), but he 

 must have done it (judging from the cylindrical hole being 

 found only a few inches from the keel) ascending from the 

 depths, and working at the hole in a nearly perpendicular 

 direction ; and if I understand rightly, all this was done while 

 the ship was sailing through the sea. 



To me the more simple explanation seems to be that one of 

 the treenail- or bolt-holes, of which there are hundreds in a 

 wooden ship, had been left unfilled. These holes are just 

 about the size and form which the one in the ship is described 

 to have been. 



XLIV. — Notice of a Fossil Hydraspide (Testudo Leithii, 

 Garter) from Bombay. By Dr. J. E. Geay, F.R.S. &c. 



Dr. Leith has drawn my attention to the description and 

 figure of a fossil freshwater tortoise which he discovered in 

 the freshwater formation of the Island of Bombay, and which 

 is admirably described and figured by my friend Mr. H. J. 

 Carter in his account of the geology of the Island of Bombay, 

 with a map and plates, in the ^ Journal of the Bombay Branch 



* See " Ship attacked by a Swordfish," Proctor's ' Light Scieace,' 

 p. 358. 



