416 Zoological Society : — 



On the coast of Sicily, according to M. Philippi, it is rare, and 

 only found between La Trezza and Aci Castello. M. H. Crosse, 

 who purposely visited this locality, found a rocky beach in which it 

 could not possibly live, and the only spot where the fishermen were 

 acquainted with it was the village of Giardini, near the sandy bay of 

 Taormina ; even there only odd valves were procured, and he says it 

 would be exceedingly difficult to obtain the animal on account of the 

 absence of tides*. . 



Capt. Guise has favoured me with the following note : — 

 " The PanopcEa was collected, together with many of the rarest 

 forms of Mediterranean Mollusca, by the Rev. L. Larking, on the 

 coast of Sicily ; the animal, when alive in a vessel of sea-water, was 

 a most lively mollusk — slashing its siphons about, and discharging 

 the water with the force of a piston." 



There appears to be no description of the animal published. 

 Philippi had not seen it, nor Valenciennes, at the time he wrote the 

 monograph of the genus for Chenu's * Conchological Illustrations.' 

 Being the type of the genus Panopcea, I was the more desirous of 

 examining it, especially as British naturalists have taken their notion 

 of Panopcea from the British shell called " Panopcea Norvegica " — 

 which it now appears does not belong to the genus, or even to the 

 same family, but must be referred to Saxicava amongst the Gastro- 

 chcBuidcB. 



In P. Aldrovandi all the visible portion of the mantle and the 

 long united siphons are clothed with thick, brown epidermis^ striped 

 with black, and very much wrinkled by the contraction of the animal 

 in alcohol : it was impossible, without dissection, to see whether the 

 orifices of the siphons were fringed as in Mya» The anterior gape of 

 the shell exhibits an oval space, perforated in the centre by a small 

 pedal orifice, scarcely large enough to admit the little finger. 



By lifting up one valve and removing the portion of the mantle 

 within the pallial line, the internal organs were seen and sketched. 



The body is large and oval, suspended by four muscles whose 

 attachments are close to those of the adductors ; it is truncated in 

 front, where it supports a small finger-like muscular foot ; behind it 

 is produced into a blunt point. 



The oral palpi are triangular and pointed, but were probably larger 

 and broader during life ; they are deeply plaited inside, with a plain 

 posterior border. 



The gills are two on each side ; the inner gills extend from the 

 base of the respiratory siphon to the palpi, between which they are 

 received ; they are deeply plaited, the plaits being in pairs, and the 

 lower edge of the gill is grooved. The inner dorsal margins are not 

 united to the body, so that the dorsal channels are only closed by 

 the apposition of the parts. 



The outer gills are simpler in structure, being formed of a single 

 series of vascular loops placed one behind another ; the free edge is 

 not grooved, and the gill terminates in front some way behind the 



* Journ. Conch, vol. ii. 1851. 



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