80 



and its congener H. tenuis. The embryo of S. sulcosa has only 

 two and a half turns visible, the nucleus appears to be covered 

 over, and is slightly oblique, as exemplified by weathered speci- 

 mens ; the last turn is longitudinally lineated, the earlier portion 

 being smooth and shining. 



This species is readily distinguished from any other Harpa of 

 the Australian Eocene by the flat area bordering the suture ; the 

 transverse lamellae are very close together, and are exceedingly 

 thin over the area alluded to. The columellar callosity is thin, 

 but sharply defined, with the formation of a deep sulcation and 

 perforation anteriorly. 



Dimensions. — Length 2.5 mm.; breadth 16 mm.; length of 

 aperture 17 mm. 



Form., and Loc. — Eocene : Muddy Creek, Victoria. 



G. 4218. Specimen having protoconch abnormally developed. 



Presented hy John Dennant, Esq^. 



G. 9337. Two examples. Purchased. 



Harpa (Eocithara) tenuis, Tate. 



1889. Sarpa tenuis, Tate, Trans. Eoy. Soc. South Aust. vol. xi. p. 151, 

 pi. vi. fig. 1. 



The anterior of the protoconch (Plate IV. Eigs. Aa-l) is slightly 

 oblique, and almost entirely hidden by subsequent turns; there 

 are two and a half of these latter, and the whole are micro- 

 scopically granulated, the later turns being also transversely and 

 longitudinally lineated. This is a larger species than S. lamellifera, 

 and it has fewer longitudinal lamellae ; the interlamellar striae, 

 both longitudinal and transverse, are not so prominent, except 

 towards the anterior portion of the body-whorl, where a species 

 of corrugation results ; the shoulder of the last whorl is roughly 

 angulate, and this is accentuated by scaly projections from the 

 lamellfe in that region. 



There seems to be a great deal in common between this and 

 H. puUigera, from the blue clays at Schnapper Point ; judging from 

 Professor Tate's figure {op. cit. pi. vi. fig. 9) it may, perhaps, be 

 regarded as an extreme form of this species. 



Dimensions. — Length 36 mm. ; breadth 22 ram. ; length of 

 aperture 28-5 mm. 



