Miscellaneous . 211 



trary, asserts positively that it does exist, the anatomist has not 

 hitherto been able to point out its precise seat. 



Swammerdam, in his ■ Biblia Naturae,' speaks decidedly of the ex- 

 istence of this sense in Helix pomatia, but offers no conjecture as to 

 its situation. Blumenbach remarks, under the head of Vermes, 

 " Several animals of this class appear to have the sense of smelling, 

 as many land-snails (Helix pomatia, &c.)," and afterwards adds, 

 "But the organ of this sense is hitherto unknown; perhaps it may 

 be the stigma thoracicum." Cuvier, in his ■ M^moire sur la Limace 

 et le Colimacon,' after remarking on the delicacy of this sense, 

 thinks it probable it may reside " dans la peau toute entiere, qui a 

 beaucoup de texture d'une membrane pituitaire." 



In investigating the anatomy of this tribe of Gasteropodous Mol- 

 lusca, I detected an organ which appeared to have been entirely 

 neglected, or has escaped the notice of those who have dissected 

 these animals. It is a depression or cul-de-sac, having its orifice 

 beneath the mouth, between the inferior lip and the anterior extre- 

 mity of the podal disc, and which in many species of different genera 

 is elongated backwards into a blind duct, more or less deep, occupy- 

 ing a situation just above the podal disc within the visceral cavity. 

 In Bulimus fasciatus it extends backwards as far as the tail, and is 

 several times folded upon itself; in Glandina truncata it extends the 

 length of the podal disc ; in the various species of Helix it is found 

 from a superficial depression to a sac the length of the podal disc ; 

 in Succinea obliqua it is of considerable length ; in Limax and Arion 

 it is a superficial depression ; in an undetermined species of Vaginula, 

 hereafter to be described, I found it half an inch in length, &c. 



It is composed of two lamina? ; a delicate lining mucous membrane 

 and an external layer, having a whitish or reddish glandular appear- 

 ance. A large nerve on each side, from the subcesophageal ganglia, 

 is distributed to its commencement, besides which it receives nume- 

 rous smaller branches along its course from the same ganglia. Its 

 arterial supply is derived from the cephalic branch of the aorta. 



This organ, from its situation, relative size to the degree of per- 

 fection of the olfactory sense, as in the carnivorous Glandina truncata, 

 &c, its structure and nervous supply, I think, is the olfactory 

 organ*. — Silliman's Journal for May 1847. 



A new species of Procellaria from Florida. By G. N. Lawrence. 



Procellaria brevirostris. — Above brownish black, beneath white. 



Bill short ; upper tail- coverts white ; lower white, tipt with ash, and 



very long ; tarsi pale yellow, marked with black at their ends for 



two-thirds their length. Length 16 inches, extent 39 inches. — Ibid. 



* Since writing the above, 1 have had an opportunity, through the kind- 

 dess of Mr. Cassin, of examining a specimen of Helix pomatia from Europe, 

 in which I find the organ in question existing as a funnel-shape depression 

 beneath the mouth, and extending backwards along the podal disc for the 

 distance of three-fourths of an inch. This I consider particularly interesting, 

 as the same species has been minutely dissected and described by Swam- 

 merdam, Cuvier and others, without any reference whatever to this cul-de- 

 sac. 



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