132 THERSITES. 



T. bipartita Fer., vi, 126. T. foreteriana Pfr., vi, 127. 



semibadia Alb. lietcera Pfr. 



f. unicolor Cox, viii, 276. /. major Dohrn, vi, 128. 



f. minor, vi, 126. T. darwini Braz., vi, 128. 



Var. semicastanea Pfr., vi, 126. 

 fimiculata Pfr. 



Section Sphterospira Morch. 



Sphcerospira MOERCH, Journ. de Conchyl., 1867, p. 256, for H. 

 fraseri, lessoni, appendiculata. For anatomy, see SEMPER, Reisen, 

 p. 160, pi. 14, f. 11 (basalis), and HEDLEY, Proc. Roy. Soc. Queensl. 

 vi, pi. 7, 8 (fraseri, blomfieldi, rainbirdi), and Proc. Linn. Soc. N. 

 S. W. (2), vi, pi. 39, 41,' 42 (broadbenti). 



Shell globose, solid, yellowish, with brown spiral lines and bands 

 or uniform chocolate-brown by coalescence of the bands ; spire ele- 

 vated, somewhat dome-shaped ; surface smooth to the naked eye. 

 Peristome broadly expanded. Type H. fraseri. (See pi. 27, fig. 4, 

 T. blomfieldi var. warroensis Hedl. PI. 27, figs. 1,2, T. rawnesleyi 

 Cox). 



Animal having the sole indistinctly tripartite ; edges of foot with- 

 out a foot border ; sides irregularly granulated ; tail convex above, 

 with an inconspicuous longitudinal impressed line ; back from man- 

 tle to head with several longitudinal grooves. Mantle bearing a 

 small triangular right body lappet and a minute left lappet. (Mit- 

 chellce). 



Jaw arcuate, strong, sculptured with broad, rather flattened ribs, 

 usually 6 to 8 in number, strongly denticulating the cutting mar- 

 gin. (PI. 32, fig. 48, T. blomfieldi. PI. 34, fig. 2, T. mitchellce. 

 PI. 32, fig. 50, T. rainbirdt). The jaw of broadbenti has 11 ribs. 



Radula having the central tooth smaller than the adjacent later- 

 als ; central and lateral teeth unicuspid, the side cusps represented 

 by a lateral continuation of the reflection, being completely fused 

 with the median cusp. Transition teeth and inner marginals hav- 

 ing a long bifid inner cusp (entocone+mesocone) and a simple, 

 small ectocone. Outer laterals tri cuspid (in fraseri, yulei, lessoni, 

 blomfieldi) or quadricuspid by splitting of the ectocone (incei, 

 mitchell>, pi. 34, fig. 1.) 



Genitalia lacking all accessory organs on the female side, the 

 duct of the spermatheca very long (pi. 33, fig. 3, .s, s, *), its upper 

 portion narrow, lower portion stout or swollen. Penis large, club- 



