THERSITES. 135 



inserted. Spermatheca duct short and arising high on the vagina 

 (pi. 32, fig. 52, pachystyla). 



The shell is more globular than that of Hadras. sir. or Sphcero- 

 spira, with smaller spire and wider columellar lip. The jaw and 

 teeth are not different from those of Sphcerospira, etc. The peculi- 

 arity of the genital system is the apparent obsolescence of the 

 epiphallus and flagellum, and the shortness of the duct of the sper- 

 matheca, which is, as a general rule, long in this genus and its 

 allies. Semper has investigated the anatomy of pachystyla, and 

 Hedley that of pachystyla and perinflata, The penis should be re- 

 examined, with a view to finding traces of the missing epiphallus 

 and flagellum, and the internal papilla. 



The species inhabit Queensland, Arnhem land and the adjacent 

 parts of the northern territory of S. Australia. T. pachystyla is 

 found on sandy ridges buried a few inches below the surface among 

 the roots of bushes, in dry weather. 



T. pomum Pfr., vi, 178. T. banneri MacGill. vi, 179. 



urvillei H. & J. T. lyndi Angas, vi, 183. 



pseudomeadei Braz. T. pachystyla Pfr. vi, 184. 



? sphceroidea Le Guill. v. daemeli v. Mts. vi, 184. 



T. nigrilabris v. Mts., vi, 179. T. jannellei Le Guill, vi, 182. 



edwardsi Cox not Bid. pachystyloides Cox. 



meadei Braz. 



Subgenus RHAGADA Albers, 1860. 



Rhagada ALB., Die Hel., 1860, p. 108, type H. reinga Gray. 

 PILSBRY, Man. Conch., vi, p. 184. WIEGMANN, Weber's Zool. 

 Ergebnisse einer Reise in Niederl. Ost-Ind. iii, p. 169 (anatomy). 



Shell small, compact, globose-depressed, narrowly or covered um- 

 bilicated, rather solid and cretaceous, whitish, unicolored or multi- 

 lineate with reddish, the supraperipheral band most prominent and 

 constant ; periphery rounded ; outer lip more or less expanded and 

 thickened, columella reflexed, partly or wholly closing the umbili- 

 cus. Type T. reinga Gray, (see pi. 27, figs. 16, 17, 18, T. carcharias 

 Pfr. PI. 27, figs. 11, 12, 13, T. supracostulata Schepm. PI. 27, 

 figs. 14, 15, T. floresiana Martens). 



Jaw (pi. 51, figs. 7, 8, T. solorensis) arcuate, with 4 or 5 unequal 

 and asymmetrically arranged strong ribs. 



Radula (pi. 51, figs. 11, 12, T. solorensis) with 126-163 transverse 

 rows of 31. 1. 31 to 38. 1.38 teeth of the type usual in Chloritisand 



