' 158 RECORDS OF THE AUSTRALIAN MUSEUM. 



Hydatina ExrGUA, sp. nov. 

 (Plate xlv., fig. 46). 



Shell minute, thin, gloV)ular, truncate above, rounded below, 

 imperforate. Colour : on a white ground are two narrow 

 peripheral chocolate bands, twice their breadth apart, connected 

 with a wash of cream, and visible internally, Sui'face smooth. 

 Within the aperture a layer of dull callus is spread on the 

 preceding whorl. Columella deeply spirally ins;erted. Apex 

 perforate, spire immersed. Height, 1'9 ; breadth, 1-5 mm. 



By size and colour pattern this diifers widely from co-generic 

 forms. 



Recent additions bring the family Ajtlustridte to have their 

 focus of di.stribution in Eastern Australia. Hydatina jjJiysis, 

 Linne, is of ordinary occurrence from Sydney northwards. H. 

 albochicta, Hoeven, was recorded by G. F. Angas from Port 

 Stephens, N.S. Wales, and latterly by J. Shirley from Stradbroke 

 Island, Queensland;''^ it is also in this Museum from Keppel 

 Bay. An example in this Museum of //. circulata, Miirtyn 

 (usually known under the younger name of //. velum, Gmelin), 

 from Port Stephens establishes another Australian record. The 

 novelty makes the fourth. BuJlina scabra, Gmelin, is common 

 in New South Wales. Shirley record.s it from Caloundra. I 

 found it at the Palm Islands, Qneen.sland, whence it ranges to 

 South Tasmania. Aplustriim ampbistre has been noted from 

 North Queensland by J. Brazier, Melvill and Standen, it has also 

 occurred to me at Green and Murray Islands. It is contended"^ 

 that this genus should he extended to embrace D'laphana brazieri, 

 Angas. From Botany Heads, N. S. Wales, Micromelo giiameiisis, 

 Quoy and Gaimard, has been reported.""'' 



H. exigua was sent to me from Tasmania by Miss M. Lodder 

 as the obscure Akera tasmanica, Beddome. Tran.sferring the 

 species to Hijdatina I used her shell for a figure. Subsequently 

 this species appeared in Sydney Harbour."* Messrs Gatliff and 



«i Shirley— Proc. Roy. Soc. Qneenslan.l, xxiii., 1911, p. 102. 



8 2 Hedley-Proc. I. inn. Soo. N. S. Wales, xxvii., 1902, p. 16, pi. iii., 

 fig. .%. 



fi' Henn — Proc. Linn. Soc. N. S. Wales, xx., 1S96, p. 5'20. 



«* Hedley— Proc. Linn. Soc. N. S. Wales, xxv., 1901, p. 7'25, fig. 22 ; 

 Op. cit., xxvii., 1003, p. 603. 



