138 PEOCEEDINGS OF TITE MALACOLOGICAL SOCIETY. 



NOTES ON THE VARIATION AND HABITS OF SCHIZOGLOSSA 

 JS'O VOSEELA IS' Die A , I'lai. 



By E. MmiDocn. 



Jicad April \Wt, 1894. 



AVrxnix the last few months I have had the opportunity of examining 

 a number of examples of Schizogloxsa Novoscelandica, and find that the 

 shell and dentition vary somewhat from that described and figured 

 by ]\lr. C. Hedley, Proc. Linn. Soc. New South Wales (2), vol. vii. 

 pp. 387-391, pis. ix.-x. The shell varies in the different forms 

 assumed by the callous thickening on the columella ; the most common 

 is a thickish callous commencing at the anterior end of the columella, 

 and spreading down to the insertion of the outer lip ; in some 

 individuals this is much thickened and forms a stout rib. 



The two small tubcrcules described by Mr. Hedley are not a 

 constant feature ; in some examples they are entirely absent ; others 

 have one, two, or several small denticles immediately in front of 

 tlie spreading callous. The young forms as well as the adult are 

 always more or less callous. 



In addition to the scar of the columella muscle, there is another 

 on the posterior end of the inner lip ; this is long and narrow and 

 immediately under the incurved margin. 



The dental formula given is 61 rows of 24-0-24. In those 

 examined by me the number of teeth per row was found to vary from 

 twenty-five to twenty-eight, with here and there a small rudimentary 

 tooth in the centre of the cleft. 



Taking the formula 26-0-26, which seems the more usual number, 

 the twenty- fifth tooth is rather smaller than the twenty -fourth, and 

 the twenty-sixth is minute and occasionally absent ; when this latter 

 tooth is present in no case have I foimd the number less than 

 twenty-six. Mr. Hedley had, unfortunately, only one or tAvo examples 

 to study ; with a larger number of specimens he could scarcely have 

 failed to note the small outermost tooth and variable number. 



The anatomy of the animal seems to sufiiciently indicate its car- 

 nivorous nature ; nevertheless, I was surprised to find that it eats its 

 own species ; in the stomach of a specimen dissected was a fairly large 

 shell, the softer structure being almost completely digested ; judging 

 from this shell the animal must have been well grown, perhaps from a 

 tliird to one-half smaller than its cannibal relative. 



Schizoglossa has a liking for Otoconcha dimidiata, Pfr., and will 

 eat this mollusc in preference to the common earth-worm. A 

 number of examples were collected in August, from near Stratford ; 

 they were found climbing the native Fuchsia ; some were six to seven 

 feet from the ground, but always protected with moss. It has also 

 been collected at Cape Egmont, "VVanganui, and Hunterville, and 

 is probably sparsely scattered throughout the greater part of the North 

 Island, New Zealand. 



