Hutton. — On some Branchiate Gastropoda. 129 



Patella argyropsis, Lesson ( — P. radians, Gml). Plate XVI., fig. e. 



Dentition. — Inner teeth simple, pointed ; outer with two denticulations 

 on the outer side, the lower sometimes semi-detached, more often rect- 

 angular ; central plate lenticular, divided longitudinally ; marginal plates 

 like those of P. olivacea, but the posterior margins smooth, and the inter- 

 mediate plate sometimes hooked. 



The specimen figured was collected at Lyttelton. P. jjholidota, Lesson, 

 has the same dentition, and can only be considered as a variety. 



Chiton pellis-serpentis, Quoy and Gaimard. PI. XVI., fig. i. 



Dentition. — 7-1-7. Ceutral tooth with a narrow neck and expanded 

 base like some of the Trochidce, the reflexed portion without cutting-points. 

 First lateral like the central, but longer. Second lateral placed obliquely 

 with a long stalk and an opaque blunt cutting-point like Nerita. First 

 marginal trilobed : second with a projecting anterior process from the 

 inner angle of which proceeds a peltate tooth on a long stalk : third and 

 fourth marginals oval ; the fifth subquadrate. 



The specimen figured was collected at Lyttelton. 



Chiton glaucus, Gray. PI. XVI., fig. f. 



Dentition. — 7-1-7. Central tooth spoon-shaped ; first lateral like Tro- 

 chidcE, with an unarmed reflexed portion : second lateral ovate with a large 

 claw-shaped cutting-point on the anterior end, and an accessory plate below 

 it : first and second marginals irregular : the third subtriangular, with a 

 large ladle-shaped tooth arising from the inner side : fourth suboval ; fifth 

 subquadrate. 



The specimen figured was collected at Dunedin. 



Acanthochites zealandicus, Quoy and Gaimard. PI. XVI. , fig. g. 



Dentition. — 6-1-6. Central tooth quadrate, the reflexed portion with- 

 out cutting-points : first lateral like the central but smaller : second lateral 

 oblique, with a long stem and a recurved portion bearing three opaque 

 dark-brown cutting-points : first marginal sub-quadrate ; second, third, and 

 fourth oval ; from between the first marginal plates springs a spoon- shaped 

 tooth. 



The specimen figured was collected at Dunedin. 



Cryptoconchus porosus, Burrow. PI. XVI., fig. h. 



Dentition. — 6-1-6. Central tooth subquadrate, longer than broad, with 

 a simple reflexed portion : first lateral curved round the central, the front 

 portion reflexed : second lateral oblique, the stalk broad and rather sigmoid, 

 the reflexed portion bearing three dark-brown opaque cutting-points : mar- 

 ginals ovate : from the first marginal there arises a spoon-shaped process, 

 and from the second a large falcate process. 



The specimen figured was collected at Lyttelton. 

 9 



