102 



C O N C II O L O G Y. 



Multi- 

 valve.--, 



LI I. 



Letas. 



elongated or contracted at the will of the animal. The 

 section contains at present only one genus. 



Genus LII. Lepas. 



Shell wedge-shaped, composed of several unequal valves, 

 Jive or more, united at the base to a cartilaginous tube. 



A. Shell composed of five pieces. 



Anatifera, 1. Analifera. Shell compressed, the two lower valves 

 large and subtriangular, longitudinally wrinkled and 

 obsoletely striated in a radiated manner from the lower 

 anterior angle ; the two superior valves long and ta- 

 pering downwards to an obtuse point ; the upper part 

 angulated on each side, top rounded ; dorsal valve long, 

 slender, and rounded ; length an inch and a half; pe- 

 dicle and connecting ligaments reddish. 

 Brit. Zo-d. tab. 39. fig. y. 

 Brit. Shells, tab. 7. 

 Found adhering to floating wood. This was the 

 shell which, in the ages of superstition and ignorance, 

 was supposed to produce the Bernacle goose. 

 Anserifera, 2. Anserifera. Shell compressed, tumid at the base, 

 larger valves striated from the lower anterior margin ; 

 the smaller valves striated from the upper posterior 

 margin ; dorsal valve compressed, slender, and brought 

 to a fine carinated edge ; length an inch. 

 Brit. Shells, tab. 166. fig. 2. 

 Found adhering to floating wood. 

 'Sulcata, 3. Sulcata. Shell compressed sub-triangular ; inferior 



valves wrought with fifteen strong diverging ribs from 

 the lower anterior angle; the front rib forms a margin ; 

 the two superior valves form a pointed apex, become 

 narrow downwards to a point, and are furnished with se- 

 ven or eight ribs, with smaller intermediate ones ; dor- 

 sal valve compressed, strongly striated longitudinally, 

 with a smooth subcarinated edge ; length about a quar- 

 ter of an inch. 



Test. Brit. tab. 1. fig. 6. 

 Found by Mr Montagu on the Dorset coast, adhering 

 to Gorgonia flabellum. 

 fascicula- 4. Fascicularis. Shell bluish-white, glossy ; large 

 r| S valves obtusely triangular, concentrically wrinkled, and 



divergingly striated from the exterior angle at the base, 

 which is dilated ; upper valves wrinkled parallel with 

 the inner margin ; dorsal valve narrow at the top, in- 

 creasing to about two-thirds of its length, where it is 

 bent suddenly inwards at the base, which is dilated; 

 apex reflected; connecting ligaments transparent; pe- 

 duncle short, thin, pellucid, smooth, and of a dusky 

 colour when the animal is alive. 



Ellis's Zoophytes, tab. 15. fig. 6. 

 First described by Ellis; afterwards found by Mr 

 Bryer at Weymouth, and by Mr Montagu on the coast 

 of Devon. We have found it in Zetland. It is usually 

 found in clusters, attached to a white gelatinous sphe- 

 rical substance, which surrounds the stalks of Fuci, and 

 even dead feathers and floating wood. The Lepas di- 

 lata of Brit. Shells, tab. 1 64, is essentially distinct from 

 the shell we are now speaking of, although it has been 

 hastily concluded to be the same. 

 Membraua- 5. Ishmbranacca. Shell with the valves connected 

 c«a, l>y broad membranes, and furnished with a short pe- 



duncle; superior valves linear, projecting, and bent 

 flownwards; inferior valves narrow, and bent back- 

 wards ; dorsal va'lve slender, about one-third of the 

 length of tiie shell ; length about half an inch. 

 Test. Brit, page 164. Sup. 

 Said to have been found on the Welch coast. 



B. Valves Numerous. 



Muki. 

 valves. 



6. Scalpellum. Shell with thirteen valves of a light S ^J"^T^ 

 brown colour, a little rough, without stria, faintly wnnk- Qi pt 

 led in some parts, and covered with short hairs ; pe- 

 duncle large, cylindric, annulated ; length five eighths 



of an inch. 



Test. Brit. tab. 1. fig. 3. 

 Brit. Shells, tab. 166. fig. 1. 

 First observed as British by Mr Boys of Sandwich ; 

 and afterwards by Mr Montagu from Plymouth. 



7. Polliceps. Shell of numerous valves, five of which p ]]j ce p S> 

 are larger than the rest; smooth and glossy ; anterior 



valve on each side ovate and convex ; dorsal valve sub- 

 ovate, thick, convex, and rounded; peduncle long, 

 with imbricated scales; length about two inches in- 

 cluding the footstalk. 



Ted. Brit. tab. 28. fig. 5. 

 Found by Mr Laskey on the shores of Iona. 



SECT. III. IMBRICATED. 



The imbripated shells are all included in one genus, imbrica. 

 They bear a near resemblance to one another in form ted. 

 and habit. 



Genus LIII. Chiton. 



Shell oblong, elliptical, convex, constructed of mam/ LIII. 

 plates placed transversely on the back of the animal, and Chiton. 

 lying upon one another at the anterior edge. 



1 . Marginatus. Shell oblong-ovate, dusky, with eight Mar „ ina . 

 valves projecting over each other in a point or beak, at tuSj ° 

 the dorsal elevation ; valves like shagreen ; border 

 rough, with a ciliated edge ; length five eighths of an 



inch, breadth three eighths. 



Liu. Trans, vol. viii. tab. 1. fig. 2. 

 Frequent upon stones covered with sea-weed about 

 low water. One variety occurs with seven valves, and 

 we have found another with only six valves. 



2. Laevis. Shell oblong, reddish, marbled, with eight Lajvis, 

 valves, elevated in the middle and minutely shagreened; 



the middle valves divided on each side into two com- 

 partments from the anterior base to the beak, the an- 

 terior division striated transversely, the posterior divi- 

 sion striated longitudinally ; border broad, striated 

 transversely and diagonally, resembling fine hair-cloth; 

 length rarely half an inch, breadth about a quarter. 

 Brit. Znol. tab. 36. fig 3. 

 This is a rare shell. It was first noticed by Pennant 

 at Loch Broom in Ross-shire ; Mr Montagu afterwards 

 found it in Salcomb bay, Devonshire ; Mr Laskey met 

 with it at Dunbar, and we have taken it in Zetland. 

 It inhabits deeper water than the preceding species. 



3. Ruber. Shell oblong, elevated on the back, red- , 

 dish, variegated, with eight valves, divided on each side, 

 from the anterior margin to the beak, into two com- 

 partments, the anterior transversely striated, the striae 

 bending and crossing the posterior compartment; spaces 

 between the stria broad ; border rough ; size of the 

 last. 



Lin.Syst. Nat. 1107. 7- 

 Common in Scotland on rocks at low water. 



4. Cinereus. Shell obioug, ovate, rounded on the ciuereiu. 

 back; greyish, with dusky stripes; valves eight, nar- 

 row ; anterior compartment striated longitudinally, the 

 posterior diagonally ; the striae are rough, so that the 



shell is shagreened; border narrow, rough; length near- 

 ly half an inch, breadth upwards of a quarter. 





