CH1TONID.E. 



CHITONID^E. 



1041 



Chilensis. 



Chiton BlainriUii. 



ft. Mantle-Border smooth, with tufts of hair at the lateral extremities 



of each plate. 



C. fatcicularis, Linnanis. Shell, apparently smooth, but when 

 examined with a glass, proving to be rough like shagreen, except 

 on the elevated dorsal ridge ; margin surrounded with tufts of 

 whitish hair, one at the junction of each valve, and two in the front, 

 making 18 in number. Colour brown or dark 

 cinereous ; length Jths of an inch ; breadth 

 rather more than Jth. Montagu, who gives 

 this description, says, that on the coast of 

 Barbary it is not unfrequently an inch long. 

 It is found under stones at low water, and on 

 stones and shells to a depth of 25 fathoms, chiton fauial , ari ,. 

 round the British shores. It ranges 



n 



northward to the shores of Norway, and southward to the Mediter- 

 ranean. Some remains of Chiton in the Crag have been referred by 

 Mr. Searles Wood to C. faicicularit. 



y. Mantle-Border hairy. 



C. Parumannt, Lamarck. Shell oblong-ovate, opaque, dirty- 

 yellowish, green, or yellowish-brown, inside white. Valves thin, 

 slightly elevated; posterior compartments of the dorsal valves a 

 little raised and striated, with minute granulated stria>, and in 

 like manner the other parts of the shell ; under each valve is 

 inserted a series of short black hairs, which lie on the back of 

 the shell. Border narrow, coriaceous, thickly set with coarse black 

 hairs. Length 2 inches, breadth 1J inch. Found under stones at 



Chiton 



MAT. HIST. DIV. VOL. I. 



Chiton spintferus. 



low water on the shores of Valparaiso Bay. There is a variety with 

 the anterior valves much narrower than the posterior. (Frembley.) 

 S. Mantle-Border beset with spines. 



C. spinosus. Shell brownish-black, valves opaque, moderate, with 

 the sides granulated, the anterior valves entirely granulated. Mantle- 

 border wide, and beset with long aculeated blackish spines, very 

 much resembling those of certain Echini. Locality, South Seas, 

 according to Pei-on. Length 3 inches. 



C. spiniferua (C. aculeatus, Barnes ; C. tulterculiferm, Sowerby, in 

 ' Tankerville Catalogue'). Shell opaque, oblong ovate, reddish-brown, 

 glossy ; inside red dish- white. The posterior angles of the valves do 

 not cover the anterior ones. Anterior valve with generally nine 

 rows of raised dots diverging from 

 the apex, but the number perhaps 

 varies with the age of the shell. 

 Second valve rather acutely beaked 

 and carinated, longer than the five 

 following, which are striated and 

 shaped alike ; these all rise into a 

 rather acute beak, are carinated, 

 each side of the carina being 

 divided into two distinct portions, 

 the anterior one the largest, and 

 bearing broad irregular longitudi- 

 nal stria} ; a prominent row of 

 raised dots, extending from the 

 apex to the anterior angles of the 

 valves, separates the compart- 

 ments ; the posterior portion 

 glossy, with fine concentric stria; ; 

 the posterior margins with tooth- 

 like granulations. Last valve 

 striated, like the anterior com- 

 partments of the others, and rising 

 into a rather prominent beak, lean- 

 ing towards the posterior margin ; 

 from under the beak are raised 

 dots, disposed in a similar manner 

 to those on the anterior valve. 

 Border coriaceous, thick, broad, 

 rough, greenish or orange- 

 coloured, and in the younger specimens thickly studded with blunt 

 spines ; but in the old shells the spines are short and scanty, and 

 generally covered with corallines; the inner edge of the border, 

 inserting itself under the posterior angles of the valves, has the 

 appearance of being deeply separated. (Frembley.) This species 

 grows to the length of 5 or 6 inches, but has then generally lost all 

 its external beauty. We have seen many individuals in all the stages 

 of growth, and have invariably found the spines of the aged ones 

 covered with that calcareous matter which is so frequently found 

 adhering to shells and submarine bodies, but we have never detected 

 anything organic about that which was attached to the spines of this 

 species. Locality, Chili and Valparaiso, where Mr. Frembley found 

 several specimens in very exposed situations ; so much so, that 

 collecting them was attended with much difficulty, and not uufre- 

 quently with danger, from the violence of the sea breaking on the 

 rocks to which they attach themselves very strongly. They are 

 generally covered with sea-weed. 



. Mantle-Border scaly. 



C. Coquimljfnsia, Frembley. Shell ovate, narrow, opaque, green- 

 ish-brown, shining ; inside blackish : the 

 anterior valves with numerous undulated, con- 

 centric ridges ; the next rather acutely 

 keeled ; the five following alike : carina 

 broad and smooth, on each side of which is a 

 similar ridge diverging from the beaks, and 

 forming with the carina a sagittate figure, 

 and connected with it by several strongly 

 marked ridges : from under the beaks 

 to the anterior angles of the valves extend 

 sharp moniliform ridges, each side of which 

 is coarsely striated longitudinally. Border 

 thick, moderately broad, and covered with 

 coarse seed-like scales, which are attached 

 laterally. Length 3 inches, breadth 1 '. inch. 

 Mr. Frembley says, that the only part of the 

 cqast where he found this species was the 

 south side of Coquimbo Bay : their habits, 

 he adds, are very similar to those of C. tspini- 

 ferut, with the exception that they seem more c , Mm ^ uMmsis 

 gregarious. 



f. Mantle-Border granulous. 



C. maynificus, Deshayes (C. olivaceus, Frembley ; C. latiis, Sowerby). 

 Shell opaque, ovate, olivaceous, dull, dotted with lighter coloured 

 spots : inside glaucous. Anterior valve with regular radiating stria:, 

 crossed by concentric ridges ; posterior margin nearly straight. Dorsal 

 valves obtusely beaked, divided laterally into two compartments, the 



3 x 



