156 Transactions. — Zoology. 



Art. XVIII. — An Enumeration of the Janellidas. 



By C. Hedley, F.L.S., Assistant in Zoology, Australian 



Museum . 



Communicated by Professor F. W. Hutton. 



[Read before the Philosophical Institute of Canterbury, 2nd June, 1892.] 



Of the components of the land molluscan fauna of New Zea- 

 land none are more striking on first appearance and more 

 interesting upon subsequent investigation than the bitentacu- 

 late slugs. They belong to an order whose extent, distribu- 

 tion, and classification appear to be but little known. Thus, 

 a writer in the Ann. Mag. Nat. Hist., February, 1874, 

 p. 90, states that this family " is found only in Australia 

 and New Zealand," and naturally draws the erroneous deduc- 

 tion of a former direct land-communication between the two 

 countries. Mr. T. D. A. Cockerell offers (Proc. Z. S., 1891, 

 p. 215) a summary of this family, remarking that he is " able 

 to classify the generic groups more clearly than has been 

 done before." His satisfaction is scarcely shared by his 

 fellow-students of the Mollusca, and some of the more flagrant 

 errors in this mischievous essay have been exposed already 

 (Ann. Mag. Nat. Hist. (6), ix., pp. 169-171). For want of 

 works of reference, the writer failed to include in a notice of 

 this family several of its members (Proc. Eoy. Soc. Queens- 

 land, vol. v., pp. 162-173). It has therefore occurred to him 

 that an enumeration and some discussion of the known forms 

 might be of interest to New Zealand naturalists. 



In the ensuing list only the valid species are numbered. 



Family JANELLIDiE, Gray, 1853. 



Synonyms. — Aneiteada, Gray, 1860; Atlioracophoridce, 

 Fischer, 1883 ; Janellina, Cockerell, 1891 ; Hyali- 

 macince, Godwin- Austen, 1882 ; Succincidce (in part), 

 auctorum. 



Descriptions. — Ann. Mag. Nat. Hist. (2), xii., p. 415; op. 

 cit. (3), vi., p. 195 ; Manual N.Z. Mollusca, p. 26 ; Land and 

 Freshwater Mollusca of India, p. 59 ; Manuel de Conchylio- 

 logie, p. 492; Genera of Eecent Mollusca, ii., p. 229; Proc. 

 Eoy. Soc. Queensland, v., p. 167; Proc. Zool. Soc, 1891, 

 p. 215; Zeitschrift fur Zool., xv., p. 83; &c. 



Obs. — The minuteness of the rachidian mentioned by 

 Fischer is not a family but a specific character. The contrac- 

 tile property of the tentacles may prove a family character. 



Classification based upon a single feature has never proved 

 to be natural — that is to say, has never arranged its subjects 



