178 SPECIFIC 



PLATE XXVIII. 



Fig. 1. Chiton porosus. 



Shell 8-valved, carinate, valves with a tooth on 

 each side, covered entirely with the marginal mem- 

 brane. 



Specimen pale olive above, sides brown ; cori- 

 aceous covering cinereous or pale brown, tomen- 

 tous ; perforated over the back of each valve with 

 a small slit and two tubular pores, one on each 

 side ; over the anterior valve four pores ; valves 

 finely striate and irregularly granulate; posterior 

 valve indented in the margin ; lateral triangles 

 marked by an obsolete fold, and terminated by a 

 small, sharp, tooth -like process. 



Habitat uncertain, but probably New South 

 Wales. 



The animal possessing this very curious multi- 

 valve shell differs from the inhabitant of Chiton 

 in the arrangement of the lungs, which do not 

 extend so far on either side, but only about one 

 third of the length ; and in the intestinal canal. This 

 dissimilarity in the worm will not however be a 

 sufficient ground for separating it from the first 



