189*.] NATiriAL SCIENCES OF PHTLADELPHIA. 85 



Family CRYPTOPLACID^. 

 Genus CRYPTOPLAX Blainville. 

 Cryptoplax striatus Lainaick. 



Abundant in Port Jackson. 



The large series of adniirahly preserved specimens submitted by 

 Dr. Cox shows conclusively the uncertainty and variability of the 

 pore bunches. In some individuals they are all developed ; in others 

 most of them are certainly absent, the minutest scrutiny of the sur- 

 face showing no trace of pores or their spicules. 



Family CHITONID^. 



Genus CHITON Linne. 



Chiton pelliserpentis Q. & G. 



Port Jackson (Cox). I am quite unable to detect any difference 

 between the excellent, fresh specimens sent by Dr. Cox and the New 

 Zealand specimens from Auckland. This is the only species of the 

 order known to me to be common to New Zealand and Australia. 



Chiton muricatus A. Ad 



The central areas have a ribless triangle in the middle ; the pleura 

 have about 10 narrow riblets on each side in front of the diagonal 

 rib, but not extending forward to the anterior margin of the valve. 

 The most prominent feature of this species is the peculiar sharp- 

 pointed girdle scales, a character unique in this genus. This species 

 was described from Sydney. Dr. Cox obtained specimens in Port 

 Jackson showing great variation in color. Angas found it at Port 

 Lincoln. 



Chiton jugosus (lid. 



A beautiful species abundant in Port Jackson. 



Chiton Coxi ii. sp. 



Shell oblong, strongly elevated, carinated, the side slopes straight, 

 Pleura loncjiindiixdhj grooved in front of the diagonal, the surface 

 elsewhere smooth. Color delicate bluish, mottled or blotched with 

 olive- brown, yellow and white. Girdle a delicate blue-green, with 

 narrow white bars. 



Intermediate valves moderately beaked; lateral areas smooth and 

 loell raised; central areas having a large smooth triangle in the 



