334 REPORT — 1864. 



Our best British malacologist, Mr. Alder, is the only one who has noticed 

 the animal of S. Turtoni. The specimen which he examined was rather 

 injured, and in a very sickly state. He says, " It was white, had a rather 

 large foot, without operculum, and a rounded head with two cylindrical ten- 

 tacles, and minute eyes at the (external or posterior) base. ITo portion of the 

 shell was covered by the fleshy parts ; but we are not prepared to say that, in 

 a state of vigour, the animal has not the power of extending some part of the 

 mantle or foot over it. The remains of the animal, examined under a micro- 

 scope, did not show any denticulated tongue." (I may add, by way of paren- 

 thesis, that Mr. Alder has, within the last few days, examined the soft parts 

 of two more individuals which I sent him for that pui'pose, but faUed to 

 detect any traces of a spinous tongue.) He has also observed that "the 

 otolites are cireula---, with a central dot, that the giU consists of a single 

 series of triangular kbes, and that the mouth breaks up into squarish angular 

 fragments, not crystalline, perhaps horny," 



In 1850, Mr. Arthui- Adams, one of the authors of a work so indispensable 

 to all students of general conchology (' The Genera of Recent MoUusca '), 

 published in the * Voyage of the Samarang ' some interesting details with 

 respect to the animal of another species of StiUfer. This species he named 

 ;S. astericola, erroneously supposing it to be identical with the one described 

 by Broderip ; but afterwards, finding out his mistake, he substituted ovoideus 

 as the specific name of his StiUfer. His diagnosis is as follows : — 



" Tentacles slender, subulate, simple. Eyes sessile at the outer bases of 

 the tentacles. Mantle enclosed. Eoot hnguiform, forming an elon- 

 gated anterior lobe, rudimentary behind." 



As will be presently seen, the animal of the European species dififers in 

 several respects from the above description. Its tentacles are thick, cylin- 

 drical, and more or less strangulated, instead of " slender, subulate, simple ; " 

 the eyes are not placed " at the outer bases of the tentacles," but behind 

 them on the neck ; the mantle is always expanded over part of the shell 

 during the lifetime of the animal, and never " enclosed," nor is it even with- 

 drawn at its death ; and so far from the foot being " rudimentary behind," 

 it is weU developed, and peculiarly constructed. The animal of S. Turtoni 

 is, besides, ciliated all over — a character which distinguishes it at once from 

 any species of EuUma, with which it has been iisuaUy associated in works 

 treating on the classification of the MoUusca. Perhaps this character may 

 have been hitherto overlooked. 



Messrs. Adams, in their ' Genera,' added some further information as to 

 the habits of StiUfer : — 



" These singular animals are parasitic in the skins of Starfishes, burrowing 

 beneath the smface, and producing tumours often of a considerable size. 

 When removed and placed in water, they do not appear to possess much 

 locomotive power, but extend the tongue-shaped foot, and use it as an 

 exploring organ." 



The ' Journal de Conchyliologie ' for 18.51 contains a notice by M. Petit 

 de la Saussaye of the present genus, and a description of a new species, S. 

 Mittrei. He added nothing to our knowledge of the animal, but attributed 

 a greater antiquity than had been supposed to the discovery of StiUfer, in a 

 purely conchological point of view, by identifying HeUv coraUhm of 

 Chemnitz as the original species. Chemnitz says that he found a dozen 

 specimens of the shell, which he had thus provisionally named, in the crevices 

 of Madrepores and other stony corals that had been collected on the shore 

 of one of the West-India Islands for the purpose of being burnt into lim e 



