2(3 MULTIVALVES. — CHITON. 



peculiar form is constituted by the attacliment of eight 

 moveable valves, which are connected by a cutaneous or 

 cartilaginous substance, capable of sufficient distention and 

 contraction, to admit of considerable action or play on the 

 part of the valves; so much so, that the animal can at plea- 

 sure convert its shell into the form of a ball, and thereby 

 assume the appearance of a little insect, well known as an 

 inhabitant of old and decayed wood. 



The covering and colouring of the valves serve to create 

 distinction ; some being perfectly smooth, others nodulous, 

 or knobbed ; some beset with spines, prickles, or hairs ; and 

 others, again, are striated, dotted, and rayed, as the C. his- 

 pidus, C. squamosus, and C. marmoratus. 



The colour of the exterior is frequently a dusky brown, of- 

 ten passing into different shades of olive-green : others par- 

 take of a reddish or pinkish tint ; whereas some specimens 

 are of an ochreous or yellowish-white complexion ; and 

 many have their valves adorned with elegant designs and 

 marblings (not unlike tattooing) in the liveliest colours ima- 

 ginable. 



The interior also admits of much variation with regard 

 to colour; however, the most prevalent is that of a blueish- 

 white, often beautifully diversified with cloudings of yellow, 

 brown, light green, and pink. 



The margin which confines the valves in their proper si- 

 tuations, differs materially in the various species : in some 

 instances, it is smooth and of a yellowish-brown colour; gen- 

 erally, however, it is beset with fine scales, of a green or 

 olive colour; frequently it is of a reddish tint, and in some 

 species it is dusky-brown, or even black. 



The situation and formation of the valves throughout the 

 genus resemble the plates which constitute a sviit of armoiu^ 

 or coat of mail ; and it is from this marked similarity that 

 the Chiton has derived its name. 



