18 POISONOUS MOLLUSCA. 



abounds in the bay of Naples, where the fishermen excused 

 themselves for not bringing it to him, saying it was a filthy 

 thing which stank abominably. When removed from the 

 sea, and placed in a vessel, there exuded a large quantity of 

 a limpid, somewhat mucilaginous fluid, exhaling a sweetish, 

 sickening, peculiar smell ; but besides this, and distinct from 

 its purple secretion, the Aplysia excretes also a milky liquor, 

 formed in an internal conglomerate gland, which seems to be 

 analogous to the kidney of vertebrate animals. As often as 

 he took the Aj)lysia from the vase of sea-water and placed it 

 on a plate with the view of more narrowly examining its 

 structure, the room was filled with a most foetid nauseous 

 odour, compelling his wife and brother to leave the room, 

 lest sickness and vomiting should follow. He himself could 

 scarcely endure it, and during the examination had repeatedly 

 to go out and breathe a purer air. His hands and cheeks 

 swelled after handling the creature for any length of time, 

 and as often as it ejaculated its milky secretion ; but he is 

 uncertain whether the swelling of the face proceeded from 

 the halitus merely, or from having accidentally touched it 

 with the hand besmeared with the liquid ; probably the latter 

 was the real cause, for when he purposely applied some of it 

 to the chin, some hairs fell from the part.* The Aplysia 

 then appears to possess the depilatory properties ascribed to 

 it by Pliny ; but it is obvious that were it indeed poisonous, 

 the odious smell amply secures the safety of those exposed to 

 its action. 



There are some less doubtful poisonous MoUusca. Delle 

 Chiaie mentions it as a fact, that the fresh-water mussel and 

 oyster become poisonous in summer, on which account their 

 sale is prohibited during that season in all southern Europe ; 

 and we, in the north, are as effectually restrained from their 

 use, by a popular tradition of their unwholesomeness in the 



This author says of the Aplysife in general : " ad nauseam usque foetidis- 

 simse," p. 72. An Aplysia which Mr. Darwin met with at St. Jago, exudes 

 an acid secretion which " causes a sharp, stinging sensation, similar to that 

 produced by the Pliysalia, or Portuguese man-of-war." — Voj/. of the Beagle, 

 iii. p. 6. 



* De Anim. Mar. 2, 7, 35, 50, 51. — " A sailor happened to take a Laply- 

 sia in the Mediterranean : it gave him such instantaneous and excruciating 

 pain as to cause an inflammation, and the poor man lost his arm ; and so 

 sensible are the tishermen of tlie poisonous quality of the mucus which 

 oozes from its body, that they will not on any account touch it." — Barbut 

 Gen. Venn. viii. I have not traced Barbut's story to its source, but he is 

 an author of littlecredit. The hurtful properties of the Aplysia have been 

 also attributed to the Tcthys. The Sea-hare of Osbeck, Voy. to China, ii. 

 114, is a ditferent and harmless animal : the Scyllsca pelagica. 



