290 STUDIES ON AUSTRALIAN MOLLUSCA, xi., 



obscure, but I observe that the shell known to New Zealand collec- 

 tors as C. scutum differs by its hollow axis from C. tenuis. 



Trochita pellucida Reeve is shown at South Kensington from the 

 Philippine Islands. It is smaller than the S. Australian shell, with 

 which it has been confused, and the interior process ends in a 

 point. 



Cerithium polygonum Sowerby. 



Cerithium polygonum Sowerby, Thes. Conch, ii., 1855, p. 854, 

 PI. 178, fig. 46. 



C. opportunum Bayle, Journ. de Conch., xxviii., 1880, p. 248. 



This species* was described from Port Essington. Bayle altered 

 the name to Cerithium opportunum, because Sowerby's name had 

 been used already in 1844 by Leymerie. Here, as in other cases, 

 Bayle's industry was superficial and abortive. The type of C. 

 opportunum, in the British Museum, was familiar to me as the 

 young of Clava nodulosa Bruguiere. For the juvenile form of this 

 I have already recorded other names (antea xxxiv., p. 439). 



Cerithium NOViE-HiBERNijE A. Adams. 



Cerithium novce-hibemice A. Adams, Thes. Conch, ii., 1855, p. 

 357, PL 180, fig. 85. 



In the British Museum is the type of this species from the 

 Hanley Collection, the original of Sowerby's figure. The locality 

 of this is given as Florida, and it is mentioned by Dr. W. H. Dall 

 as a synonym of C. eburneus Say.* So it is unlikely that the record 

 by Melvill and Standen of this species from Murray Island, Torres 

 Strait, is correct, t 



Clava bituberculata Sowerby. 



Cerithium semigranosum Lamarck, Anim. s. vert., vii., 1822, p. 

 72; Id., Ency. Meth., PI. 443, fig. 1; Id., Kiener Cerite, 1843, p. 26, 

 P1.21, fig.2. Not Cerithium semigranosum Lamarck, Ann. du Mus. 

 iii., 1804, p. 437. 



* Dall, Bull. U. S. Geol. Survey, No. xxiv., 1885, p. 64. 

 t Melvill & Standen, Journ. Linn. Soc. Zool., xxvii., 1899, p. 167. 



