Iredale.— Suter' s "Manual of the New Zealand Mollusca." 473 



Dr. Dall courteously wrote me that he was really not well acquainted 

 with these, and hoped that Antipodean workers would deal with them. 

 Previous to the receipt of this letter I had proposed Lepsiella for Purpura 

 scobina Quoy and Gaimard and Neothais (typographical error, Neothias) for 

 Purpura smitki Brazier. 



Suter has synonymized Lepsia Button, 1884, with Thais Bolten, 1798, 

 as an absolute synonym : he then admitted (p. 423) Stramonita Schumacher 

 as a subgenus, to which he allotted the species succinate (Martyn) and 

 tritoniformis (Blainville), not quoting any synonyms, though the latter 

 species has a generic synonymy of its own. A third subgenus, Nucella 

 Bolten, is recognized, and thereto is added the species striata (Martyn) and 

 scobina (Quoy and Gaimard). This sequence cannot be recommended, 

 as the conchological relationship of T. succinata (Martyn) and T. striata 

 (Martyn) is much greater than that between the former and T. tritoniformis 

 (Blainville), or between the latter and T. scobina (Quoy and Gaimard). 

 Suter has classed T. haustrum (Martyn) in the same subgenus as T. neri- 

 toides Bolten. and has quoted TroscheFs description and figure of the radula. 

 It might be of use to the Neozelanic student to outline TroscheFs classifi- 

 cation, as this was prepared solely from radular characters, no value at all 

 being given to shell characters. I suggest that a careful consideration of 

 radular characters in conjunction with shell features as governed by growth 

 would lead to a satisfactory arrangement. Troschel admitted five genera, 

 thus : — 



Thais nodosa L. (neritoidea Lain.). 



Purpura patula L. 



Tribulus hippocastanum Lam. 



deltoidea Lam. 



pica Blainv. 



mancinella Lam. 



- bitubercularis Lam. 

 Polytropa la pill us L. 



- dubia Kr. \schultzei Dkr.). 



haustrum Q. & G. 

 Stramonita chocolata Duclos. 



— floridana Conr. 



bicostalis Lam. 



uridata Lam. 



haemastoma L. 



rustica Lam. 



blainrillei Desh. 



consul Chem. 



This arrangement cannot be confidentlv criticized, as it has been shown in 

 other groups that the nomination of the species was very inaccurate. In 

 order to emphasize, the fact that shell characters and radular characters do 

 go hand-in- hand. I would note that all the five species Troschel grouped 

 under Tribulus were associated together, from shell characters, by H. and 

 A. Adams in their subgenus Thalessa (Gen. Rec. Moll., vol. i, p. 127, 1853), 

 and, further, that out of the eight Troschel named in Stromonita six appear 

 under the same subgeneric name in H. and A. Adams's work. Further, 

 Troschel placed haustrum in a different genus from neritoides, associating the 

 former with the British lapillus. Almost as bad is Dall's subordination of 

 Trochia Swainson to Nucella Bolten. which he used for lapillus L. L T pon 



