160 PSEUDOVAKICIA. 



The phenomena connected with the columella, though roughly 

 indicated in the figure accompanying Professor Tate's description, 

 seem to need further explanation. Although the pillar is smooth, 

 yet even in the brephic stage it is seen to be slightly twisted, 

 a character perpetuated through the neanic stage, though not 

 prominent until the ephebic stage was attained, when a small, 

 inconspicuous fold was developed with another just visible on 

 the margin of the columella anteriorly. It was not until the 

 extreme ephebic or, perhaps, the commencement of the catabatic 

 stage, however, that these two folds or corrugations became well 

 developed, and their accentuation, as seen in the largest specimen 

 in the Museum (larger than that described by Professor Tate) 

 appears to be due to senility. It somewhat resembles Andonia, 

 Harris and Burrows, from the Upper Tertiaiy of Italy and the 

 Eocene of North- Western Europe, but the nature of the protoconch 

 and the peculiar development of the varices are highly distinctive. 



Type. — Fseuduvaricia mirahilin, Tate. 



Pseudovaricia mirabilis, Tate. 



18S8. Pseudovaricia mirabilis, Tate, Trans. Eoy. Soc. South Aust. vol. x. 

 p. 146, pi. vii. figs. 9a-f. 



Protoconch (Plate VI. Figs. \a-l) composed of two and a half 

 broad and narrow, slightly angulate turns flattened at the apex; 

 smooth, but bearing microscopic spiral lineations and longitudinal 

 strife, best developed on nearing the shell proper. It is almost 

 impossible to define the precise limits between the protoconch 

 and the brephic stage ; the longitudinal striae run in sets divided 

 by the varices, and the striations undoubtedly begin on the 

 protoconch, though they are extremely minute to commence 

 with. In that vicinity the "varices" are close together, and 

 are mere striae larger than the others. As this is the only species 

 hitherto described as belonging to the genus, much of what has 

 been said in the generic review applies specifically also. In 

 addition, it may be mentioned that the shell is composed of 

 seven slowly-increa.sing whorls, flatly convex, with a very narrow, 

 high-sloping shoulder defined by a strong thread. The whole 

 surface is finely transversely striated ; the strite become larger 

 near the suture and prominent on the body-whorl anteriorly. 



