1 7S SPECIFIC 



PLATE XXVIIl. 



Fig. 1. C HiTos porosus. 



Shell S-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 ex- 

 tend 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 



