328 Proceedings of tJie Roi/al Societ// of Victoria. 



interesting to note that some of tlie Muddy Creels, examples of 

 this species show regular rusty oval rings and patches especially 

 on the sutural band, and other rusty mai'kings in conformity 

 with the sinus at fairly regular intervals, apparently a remnant 

 of original colour markings. I name this species with much 

 pleasure after Mr. A. R. C. Selwyn, the first Government 

 geologist of this colony. 



Variety laevis, var. nov. (PL XIX., Fig. 2). 



There is another form which I can only regard as a variety 

 of the above, showing a marked tendency towards the almost 

 entire suppression of the strong spiral threads or lirae, thus 

 intensifying the general biconic aspect of the shell. 



Apiotoma bassi, sp. nov. (PL XIX., Fig. 11). 



Description. — Shell fusiform, with a tapering spire less than 

 half the length of the shell, a small but mammillate apex, 

 whorls angulatod by one strong keel, the base of the shell at- 

 tenuated into a long, straight open canal, and a comparatively 

 narrow aperture. 



Embryo consisting of from one and a-half to two smooth 

 whorls with the tip obliquely immersed, giving rise to the blunt 

 mannnillate appearance of the apex. Whorls number seven or 

 eight, except in young specimens, strongly angulately keeled 

 about the middle of each whorl or more usually a little above 

 the middle of each whorl. On the earlier whorls the keel is 

 bluntly nodulose ; the nodules tend to become obsolete towards 

 the body-whorl, where they are rarely present. The slope be- 

 tween the posterior suture and the keel is somewhat concave, 

 intensifying the padoga-like appearance of the spire, suture 

 well-defined and inclined to be margined. Surface of the shell 

 covered with fine frequently interrupted spiral threads of 

 unequal strength, crossed by stronger lines and undulations of 

 growth, which frequently interfere with the regularity of the 

 spiral threads. Sinus broad, moderately deep, and situated at 

 the greatest concavity of the slope between the suture and the 

 keel. Aperture long and rather nan-ow and gradually tapering 



