43 



ON SOME TASMANIAN PATELLIDyE. 



By the Rev. J. E. Tenison Woods, F.L.S., F.G.S. 



IBead 9ih May, 1876.] 



Our knowledge of Australian mollusca is almost confined to 

 descriptions from the shells alone. Nearly all that we do 

 know of the animals inhabiting the shells has been given to 

 us by Messrs. Quoy and Gaimard in the voyage of the 

 Astrolabe, where the plates as far as they go, leave but little 

 to be desired. In the Nudibranchiate section Mr. G. F. 

 Angas, F.L.S., etc., has done good service. But the greater 

 part of the field remains untrodden. I propose in this paper to 

 give a more detailed account than has yet appeared of the 

 shells and animals of some Tasmanian Patellid^. I choose 

 this family because it is the one in which a knowledge of the 

 animal is most required to arrive at correct principles of 

 classification. Limpets cannot be determined from the shell 

 alone. The genera are classed according to the respiratory 

 organs of the animal. These can only be told by a study of 

 the habits of the animal, and by dissection. To both of these 

 methods I have given lately some attention, and a part of my 

 conclusions are embodied in the present paper. 



Before giving a glance at the character of the genera, let me 

 state the principles which have guided me in the nomencla- 

 ture. Conchology has recently increased its synonyms with 

 a rapidity which is perfectly appalling. No naturalist can 

 deprecate too strongly the practice of lightly changing a re- 

 ceived name. It is embarrassing, nay, disheartening to 

 students, and destructive of progress in science. This is not 

 the place to enter into the causes of the evil, but it is in part 

 due to a misunderstanding of the labours of Dr. Hermannsen, 

 Chenu, and others, as embodied in the Manual of Conchylio- 

 logie. I shall adhere strictly to the British Association rules, 

 and notably not to admit " priority " for pre-Linnean names, 

 nor for those where no definition or figure has been given ; 

 and, even in the cases not thus exempted, not to change the 

 name if it be generally received and known among naturalists. 



For those reasons I shall adhere to Eschscholtz's genus of 

 Acmvta instead of Teclura. First, because Messrs. Auduoin and 

 Milne Edwards gave no definition of their genus, and secondly, 

 because Acmaea is the name by which it is described in the 

 works of Professors Forbes, Hanley, Woodward, Chenu, 

 Carpenter, and the earlier writings of Mr. Angas. 



Limpets, or bonnet shells (PatellidoB from Patella, Latin for 

 a little dish) are classified according to the respiratory organs 

 of the animals which inhabit them. This is true at least for 

 the only genera known in Australia. 



