147 



Latirus subundulosus, Tate (sp.). 



1888. Perisier/iia subundulosa, Tate, Trans. Eoy. Soc. South Aust. vol. x. 



p. 159, pi viii. fig. 12. 

 1893. Peristcrnia subundulosa, Tate and Dennant, id. vol. xvii. pt. 1, p. 219. 



This so closely resembles L. interlineaius that it might almost 

 be regarded as an extreme form of that species; the whorls are 

 more regularly convex, the spiial ridges more flatly rounded, 

 and there are other minor differences in the ornament which led 

 its author to regard L. subundulosus as a distinct species. 



Dimensions. — Length 23mm.; breadth ITS mm.; length of 

 aperture 8 mm.; length of canal 6-5 mm. 



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



G. 9461. Three specimens illustrating stages of growth. 



Purchased. 



Latirus tatei, sp. nov. 



[Plate V. Figs, la-b.'] 



Shell small, fusiform ; protoconch smooth, composed of two and 

 a half turns, the earlier portion being lateral and very small, 

 the suture is bordered by a slightly elevated keel seen only in 

 well-preserved specimens, surface microscopically granulate ; the 

 anterior portion of the protoconch is at first somewhat inflated, 

 and then becomes constricted and longitudinally striated as it 

 passes into the brephic stage ; spire moderately elevated, with five 

 sliort, convex whorls; ornament consisting of widely distant, broad, 

 obtuse costse, extending from sutui-e to suture, except over the 

 narrow, undulating, striated band bordering the suture posteriorly, 

 regarded from above the whorls appear polygonal, commonly 

 hexagonal ; the body- whorl in the adult is frequently deprived 

 of these, but is furnished witli a thick, almost varicose anterior 

 margin ; surface of the shell strongly spirally lineate, a thin 

 lineation alternating with a bolder one in the later stages of 

 growth, the interruptions of the lines of growth producing a 

 semi-granulate and undulating appearance ; aperture ovate, broadly 

 channelled in front ; outer margin thick, lirate within, the callosity 

 being continued round the acute posterior channel and terminated 



