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Distribution. — It is remarkable that the whole of the known 

 species of this interesting genus have been described from South 

 Australia. Up to the present I believe there are only two 

 records of the occurrence of members of this genus in the other 

 States. Stenochiton pallens, Ashby, from Port Phillip Heads, 

 Victoria, wrongly identified by Sykes (Proc. Mai. Soc, vol. ii., 

 pt. 2, July, 1896) as S. juloides, Ad. and Ang., and correctly 

 identified by Gatliffe and Gabriel (Proc. Soc. Vict., 30 (N.S.), 

 pt. i., 1917, p. 26), one specimen only. And S. juloides three 

 valves only in shell-sand, Albany, W.A. (Terr: Trans. Roy. 

 Soc, S. Austr., xxxv., 1911, p. 96). The other localities given 

 by Hedley (in Jour. Roy. Soc. W. Austr., vol. viii., 1914-1915, 

 p. 23) have probably been copied in error from the records of 

 the next species in Torr's paper. We have, therefore, the 

 remarkable fact that outside of the two occurrences above 

 referred to, no representatives of this interesting genus have so 

 far been found outside of South Australian waters. 



Habits. — Bednall (in Proc. Mai. Soc, vol. 88, pt. 4, 

 April, 1897, p. 142) gives the habitat of the few specimens of 

 S. juloides that had then come under his notice, "found living 

 on Pinna shells below low-water mark." And on the same page 

 he records the fact that the specimens he describes under the 

 name of S. fAlsbryanus were found on "seaweed (Zostera), 

 Troubridge Shoal, St. Vincent Gulf." Dr. Torr (Trans. Roy. 

 Soc, S. Austr., vol. xxxvi., 1912) states that he had collected 

 S. juloides by dredging and in shell-sand, and quotes Mr. 

 Riddle as having found specimens on "old boots and bottles, 

 and especially near the roots of Zostera, by dredging or with 

 grappling iron — they are rarely found in shallow water." And 

 on the same page he records having taken specimens of Steno- 

 chiton pilsbryanus, Bednall, "on Zostera (sea-weed)." And 

 again, "Two large specimens by Mr. F. L. Saunders on sea- 

 weed at Aldinga," and "near the roots of Zostera at Wool Bay 

 and other places by Mr. Riddle." I am now able to throw a 

 good deal of light on the habits of members of this genus. The 

 discovery of Stenochiton juloides, Ad. and Ang., on bottles, 

 boots, etc., is evidently purely accidental. They live on the 

 marine plant belonging to the order Fluviales known as 

 Posidonia australis. I have found them in many localities at 

 the base of the long ribbon-like leaves of this well-known plant. 

 During the last week of December last, at Normanville, in this 

 State, in company with Mr. F. L. Saunders, who with his 

 brother had taken them in the same locality in numbers before, 

 I was able by means of a strong digging hook to get well down 

 into the roots of the Posidonia, and found enclosed in the 

 brown sheaths of past leaves which enwrap the underground 

 stems of that plant a large number of this Stenochiton. The 

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