Mem. Nat. Mus. Vict., 15, 1947 



RECORDS OF ONCHIDIIDAE (MOLLUSCA, 

 GASTROPODA) FROM VICTORIA. 



By J. Hope Macpherson B.Sc., Conchologist, National Museum 



of Victoria. 



(Eeeeived for publication July 7, 1947). 

 Plate 14. 



These notes record two species of Onchidiidas from the Vic- 

 torian coast, and give some observations regarding their habitat 

 and habits. 



The family Onehidiidaa is chiefly a tropical and sub-tropical 

 one (Pacific and Indian Oceans), though a few species straggle 

 into the temperate zones of both the Northern and Southern 

 Hemispheres. From the latter, six species have been recorded 

 from New Zealand by Powell (3), one of which, OnchideUa patel- 

 loides (Q. and G.) has also been taken in Tasmania by Bretnall 

 (1). Until recently (2), no records of Victorian Onchidiidae had 

 been published, but within the last two years, the National 

 Museum has collected examples of two species within the State. 



Onehidina australis Semper, 1882. 



Onehidina australis Semper. Reis. im Arch. Phil., III. Land- 

 moll., VI., 1882, p. 287. 



In February 1946, specimens of this species were collected by 

 the author at Wingan Inlet, East Gippsland. The upper shores 

 of the Inlet are cstuarine mud flats with typical flora. The 

 Onehidina were found about thirty feet above high tide mark 

 feeding on Tetragonia expansa Murr. ; the colony consisted of some 

 hundreds of individuals. They were strictly nocturnal, feeding 

 only at night, retiring during the day under bark, driftwood, or 

 other debris. 



On a second visit made to the Inlet in June 1946 it was found 

 that the Tetragonia had died down, and that no Onehidina were 

 in its immediate vicinity. However, on turning over partly 

 submerged logs on adjacent open mud flats, the animals were 

 seen to be hibernating on the damp undersides of the logs or bur- 

 rowing into the mud beneath. 



Specimens kept in a vivarium at the National Museum are 

 strictly nocturnal, retiring to their burrows or under debris 

 during the day. This confirms the field observations noted above. 



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