BULLA. 277 



or tubular, but have the aspect of loose muscular straps ; they 

 however spring from two small yellow spongy or granular 

 bodies, situate on the upper part of the gizzard; these I pre- 

 sume are the salivary glands ; if so, the straps are the excre- 

 tory ducts. They lie on each side the oesophagus in the most 

 lax manner : I should have called them cesophageal, gizzard 

 and buccal mass retractors, as they are connected with all 

 these organs, if M. Cuvier had not determined them to be 

 salivary glands ; but he is in error in stating, " ~L'hydatis les 

 a tres longues, inegales, et celle du cote gauche fourchue par 

 son extremite posterieure." We have in our cabinet perfect 

 preparations of these organs, and can positively state that they 

 are of the same length, entirely symmetrical, with both ends 

 fixed to the gizzard and posterior part of the buccal mass ; 

 they do not float loose, of different lengths and forms, as 

 represented in pi. 2. fig. 14. of M. Cuvier^s memoir. Having 

 dissected numerous specimens we are quite sure on this point. 

 Though we admit the straps to be the salivary glands, sub fide 

 Cuvieri, still we are much astonished that that great naturalist 

 has not noticed the very visible dendroid leaflets on each side 

 the mouth ; we must consider them an additional pair of sali- 

 vary glands : some mollusca have an upper and lower pair, 

 and these would appear to be more adapted for such purpose 

 than the slender strap-shaped filaments. I can only account 

 for their not being noticed, on the supposition that the glan- 

 dular leaves in M. Cuvier* s specimens must have been so 

 discoloured by the spirit as to have escaped attention. One 

 word more on them : as they are situated exactly at that part 

 of the groove which corresponds with the position of the 

 oesophageal ganglions, it is possible that, as these nervous 

 masses are of larger volume than I ever saw in any other gaste- 

 ropod, the glandular leaflets may excrete a liquor to invigorate 

 and minister to the nervous influences : this is a mere conjec- 

 ture : I certainly incline to regard them as salivary glands. 

 Mr. A. Hancock thinks that the leaflets I have mentioned are 

 olfactory organs : I altogether dissent from this opinion. 



Having mentioned the nervous system, it may be as well at 

 once to notice it, as M. Cuvier scarcely alludes to it. From 



