66 



MOLLUSCA. 



[Gasteropoda 



This shell has much the aspect of the following species, but 

 differs in the margin being much broader, the whole shell being 

 much more oblong, in the valves being longer in proportion to 

 their breadth, and also in being more elevated in the middle 

 than that shell. 



Found at Nevvhaven, Mid Lothian, adhering to an oyster, by 

 General Bingham. The late Rev. Dr. Goodall, Provost of 

 Eton College, found this very elegant species at extreme low 

 water-mark, on a stone at Tor Abbey rocks. In his specimen 

 the valves were of a dark liver-coloured brown, with a double 

 spot of pale green on each ; the transverse stria?, which pro- 

 duce the shagreened appearance, were exceedingly minute. 

 He had mistaken it for the C. laevis. The magnificent speci- 

 men from which fig. 15 as well as fig. 12 were drawn, were dis- 

 covered at Oban, Argyleshire, and presented to me by my late 

 friend Captain Charles Carmiehael, an accurate and zealous 

 naturalist. 



6. Chiton ruber, pi. XXI, f. 6 and 9. 



Chiton ruber, First Ed., pi. 35, f. 6 and 9 ; Lowe, Zool. 

 Journ., II, p. 101, pi. 5, f. 2 ; Brown, Ency., p. 401 ; Forbes, 

 p. 37. 



Shell carinated ; valves broad, quite smooth, polished, and 

 shining, destitute of punctures or granulations, but with nume- 

 rous, rather faint, irregular, transverse stria;, or lines of growth, 

 which are more determinate on the sides of the valves, where 

 they are longitudinal ; margin broad, with irregularly granose, 

 or farina-like dots; whole surface with bright reddish-brown, or 

 burnt sienna-coloured clouds, spots, or undulations ; marginal 

 fringe of a light red-colour, and not very distinct; middle valves 

 provided with two marginal teeth ; first valve with nine teeth, 

 and the terminal one with ten. Length three-eighths of an 

 inch ; breadth about a quarter. 



Found in deep water in the Frith of Forth; on the coasts of 

 Argyleshire, Yorkshire, Northumberland, and Durham ; and 

 Lough Strangford, Ireland. It is a rare species. 



7. Chiton marginatum, pi. XXI, f. 3. 



Chiton marginatus, First Ed., pi. 35, f. 3 ; Pennant, IV, p. 

 71, pi. 36, f. 2 ; Montagu, p. 1 ; Maton and Rackett, p. 21, pi. 

 1, f. 2; Brown, Wernerian Mem., II, p. 503; lb., Ency. Brit., 

 p. 403; lb., Popular Ency., II, p. 378, pi. 17, f. 103; Chiton 

 cinereus, Lowe, Zool. Journ., II, p. 99 ; Forbes, p. 37- 



Shell a little carinated, ovoid; valves but slightly beaked; 

 whole surface covered with regular, shagreen-like granulations ; 

 colour various, frequently dusky, or drab, and sometimes mot- 

 tled; marginal ligament with five meal-like, irregular papilli, 

 its edges with a minute fringe of a dusky brown-colour ; the 

 first valve with about ten marginal teeth, and the terminal one 

 with twelve. Length about five-eighths of an inch; breadth 

 three-eighths. 



Found in deep water on many of the British coasts, namely, 

 Devonshire, Dorsetshire ; Friths of Forth and Clyde ; and 

 Dublin Bay, Ireland. 



8. Chiton cinereus, pi. XXI, f. 18. 



Chiton cinereus, First Ed., pi. 35, f. 18; Montagu, p. 3; 

 Fleming, p. 289; lb., Ency., p. 102; Brown, Ency. Brit., p. 

 402; Maton and Rackett, p. 22, pi. 1, f. 3; Forbes, p. 37. 



Shell oval, broad in proportion to its length, the first and 

 terminal valves broadly rounded ; valves very slightly elevated 

 in the centre, with blunted beaks ; whole shell with fine, irre- 



gular shagreen ; margin with irregular, elevated papilli, and 

 slightly fringed at the edge ; whole surface, including the mar- 

 gin, of an uniform dusky ash-colour. Length somewhat more 

 than a quarter of an inch; breadth not so much. 



Found on the coasts of Weymouth and Poole, adhering to 

 rocks and oysters ; and has been met with in the Frith of 

 Clyde. 



9. Chiton fuscatus, pi. XXI, f. 17- 

 Chiton fuscatus, First Ed., pi. 35, f. 17. 



Shell oval, of a dusky brown-colour ; the valves but little 

 elevated, and slightly pointed ; their surface, as well as the 

 marginal ligament, — which is very narrow, — covered with fine 

 shagreen-like papilli ; and the outer edges of the valves with 

 longitudinal stria 1 ; destitute of a fringe on the edge of the bor- 

 der. Length nearly three-quarters of an inch ; breadth about 

 five-eighths. 



Found adhering to oysters in the Frith of Forth; and under 

 stones, at very low water, at Crammond, Ireland. 



10. Chiton Albus, pi. XXI, f. 2. 



Chiton Albus, First Ed., pi. 35, f. 2 ; Montagu, p. 4 ; Maton 

 and Rackett, p. 22, pi. 1, f. 4; Fleming, Brit. An., p. 290; lb., 

 Edin. Ency., p. 103 ; Brown, Ency. Brit., p. 402. 



Shell oval, white ; with the valves but little raised, short in 

 proportion to their breadth, and very slightly pointed ; whole 

 surface covered with minute punctures ; border rather dusky, 

 with decussated stria;, producing a fine shagreen-like appear- 

 ance, when viewed through a strong lens, and destitute of a 

 fringe on its edge. Length three-eighths of an inch ; breadth 

 somewhat less. 



Found on oysters in the Frith of Forth, and at Poole, Dor- 

 setshire, and is invariably a deep water species. 



11. Chiton Asellus, pi. XXI, f. 14 and 19. 



Chiton Asellus, First Ed., pi. 35, f. 14 and 19; Ency. Meth., 

 pi. 161, f. 12; Lowe, Zool. Journ., II, p. 101. 



Shell subcarinated ; valves slightly beaked, covered with 

 moniliform, or chain-like granulations, disposed in the form of 

 longitudinal, slightly oblique striae ; marginal ligament rather 

 broad, with black, shagreen-like granulations, and provided with 

 a slight fringe ; the whole of the valves destitute of marginal 

 teeth, but with their internal edges minutely crenulated, or 

 granulose ; colour variable, sometimes chocolate-brown, and at 

 others olive-green. Length about three-eighths of an inch ; 

 breadth somewhat more than a quarter. 



Lowe says, " in young specimens the posterior edges of the 

 valves are dark brown, or black, which extends over about half 

 the valve ; in older shells this colour becomes deeper, and ex- 

 tends gradually over the whole of that part of each valve, which 

 is covered by the preceding as the shell contracts in drying." 

 Fig. 14 is a greatly magnified figure of a specimen, sent to me 

 by Captain Carmiehael, in which the valves are green, and the 

 border brown. 



This species is found near Oban, on the Argyleshire coast. 



12. Chiton Aselloides, pi. XXI, f. 21. 

 Chiton Aselloides, First Ed., pi. 35, f. 21. 



Shell ovoid, carinated; valves with a slight beak, the first and 

 terminal ones with eleven or twelve teeth, middle ones with two 

 each ; whole surface covered with minute, regular granulations, 

 but not beaded as in the preceding species ; margin black, with 

 coarse raised granulations ; fringe very short, and indistinct ; 



