XV111 POLYPLACOPHORA. 



cannot be given priority, save in the case of Cryptochiton ; the other 

 groups are all incongrous assemblages. 



From this time, no work of importance was done on Chitons 

 until 1863, when PHILIP P. CARPENTER (born in Bristol, England, 

 in 1819, died at Montreal, Canada, 1877) published a catalogue of 

 the West American forms (Brit. Asso. Rep). This was followed by 

 many articles upon the Californian and Atlantic Chitons, and 

 finally by the preparation of a monograph of the entire group. In 

 his work upon this great undertaking, Dr. Carpenter examined 

 critically the Cumingian and British Museum collections, contain- 

 ing most of the types of Broderip, Sowerby, Gray, Reeve and H. 

 Adams; and besides, nearly every collection of any size in England 

 and America, including those of A. Adams, Angas, Dr. A. A. Gould, 

 Newcomb, Jay, Haines, the State of California, the Smithsonian 

 Institution, Museum of Comparative Zoology, etc. The information 

 gained from the examination of this great amount of material was 

 in process of re-arrangement at the time of his death, in 1877, that 

 relating to the Leptoidea and Ischnoidea being practically com- 

 pleted. A vast amount of work had been done upon the other 

 groups, but his studies of them were far from finished. A large 

 number of drawings had been prepared under Dr. Carpenter's 

 direction, mainly by Messrs Emerton, Foord, and Smith. The 

 whole of this MS. being devised to the Smithsonian Institution, 

 Dr. WM. H. DALL published (Proc. U. S. Nat. Mus. 1881, p. 283- 

 292) an A bstract of all the genera of Chitons, giving Carpenter's 

 complete classification, and brief diagnosis of the new groups. 

 Most of the Carpenterian names therefore date from this time; 

 although in 1873 a large part of them were included by Carpenter 

 in a table printed by the Smithsonian Institution, showing the 

 characters of the " Regular Chitons. " The fact that the distribu- 

 tion of this table was limited to Carpenter's personal friends and 

 correspondents, that it was never advertised or offered for sale, was 

 not sent to most (if any) public scientific libraries nor noticed in 

 scientific journals, prevents us from dating his names from the time 

 of its publication. 



The following table shows the Carpenterian classification in full. 

 The group and family names given by DALL in 1889 (' Blake" 

 Gastropoda) are added in parenthesis. 



