MOLLUSCA. 39 



23. FICULA, Swainson. 



Head elongated, slender, flattened ; tentacles long, subulate, placed at the sides of the 

 front, separated by a wide interval at their base ; eyes large, black, and sessile on the outer 

 side of the base of the tentacles ; siphon elongated, subcylindrical, and produced ; mantle 

 thin and membranous, produced on each side into a rounded lobe equally reflexed on each 

 side over the shell ; foot large, expanded, rounded in front, rather produced on each side of 

 the front edge, expanded, broad and tapering, and not furnished with any operculum. 



1. Ficula l^vtgata. PI. IX. Fig. 4. Peeve, Conch. Icon. Ficula, pi. 1. f. 4. Bulla ficus, Linnaeus. 

 Pyrula Jicus, Lamarck. Head and neck pink, varied with scattered yellow spots, mantle bright pink, 

 mottled with white and darker pink ; under surface of foot dark purple chocolate, varied with yellow 

 scattered spots. 



Hab. Sooloo Sea, at the depth of thirty-five fathoms. 



The dark chocolate colouring of the under surface of the foot presents a rich contrast 

 with the bright freckled pink of the upper. 



2. Ficula reticulata. PI. IX. Fig. 5. Eeeve, Conch. Icon. Ficula, pi. 1. f. 1. Pyrula reticulata, 

 Lamarck. Head and tentacles white, mantle light pink, marbled and reticulated with darker pink ; foot 

 pink, with sis large opake white spots at about equal distances. 



Hab. West coast of Borneo ; from mud at a depth of about seventeen fathoms. 



The head of this species differs from that of the former in being colourless. The mantle 

 is characterized by the same pink reticulated marbling as the foot. 



The Ficula is a very lively animal when observed in its native element, crawling along with consi- 

 derable velocity, and, owing probably to the lightness of its shell, able to ascend the sides of a glass vessel, 

 in which I had it captive, with facility. The proboscis is rarely exserted when the animal is in motion, 

 but the Ions; slender tentacles are stretched out to their full extent. A. A>. 



J 5 



24. PLEUROTOMA, Lamarck. 



The animal of Pleurotoma has rather a short flattened body, with the foot notched in 

 front, and the two angles produced on the sides ; the posterior part is rounded and bears a 

 small, semitransparent, horny operculum, with concentric elements. The head is very long, 

 flattened, and but little produced in front ; the tentacles are subulate and close together at 

 the base, and the eyes are near the outer side of the tip, which latter tapers off beyond them. 



The Pleurotomce generally inhabit deep water and crawl rather quickly. 



1. Pleukotoma impages. PL IX. Fig. 1 a, b. Pleur. testa clavato-turrita, solidiuscula, anfractibus 

 novem ad decern, medio tumidiusculis, concentrice obscure plicato-rugatis, canali brevisshno, truncate, 

 apertura oblonga, labro leviter emarginato ; albida, carneo-fuscescente suffusa, inter rugas saturatiore. 



