MOI.LUSCA FROM KUiHTV FATHOMS 11 KDI.KV. 291 



A few specimens. 



Most of the genus are cancellate ; the present with C. carinata, 

 Hedley' and C. (jlabella, Murdocli', are smooth. The latter is re- 

 markable for a double basal funicle. In C. naficoides a second 

 fuiiicle appears to exist also, but the inner is swallowed by the 

 umbilicus and its presence is only indicated by the callus on the 

 aperture. The outer funicle is unusually faint, the basal aspect 

 of a young shell (PI. liv., fig. 7) exhibits the best developed funicle 

 before me. 



ClTHNA AN(;ULATA, Sp. itOV. 



(Plate Iv., fig. 16). 



Shell small conical, thin polished perforate. Colour : some in- 

 dividuals milk white, others hyaline with a yellow apex. Whorls 

 fi\e, compactly coiled, with rather fiat sides, parted by deeply 

 impressed sutures. Protoconch not particularly distinguislied. 

 Sculpture : a sharp elevated cord accentuates the peripheral keel, 

 abo\e it and on the spire occur a few faint irregular radial ribs. 

 Apeiture pyriform, anteriorly sul>channelled, outer lip produced 

 medially, thin at the edge, but fortified remotely by a slight ex- 

 ternal rib varix. Columella long and nearly straight, its refiec- 

 tion reaching partly over the umbilicus. Base rounded. 

 Umbilicus variable, best shown in adults, a narrow furrow cir 

 cumscribed by a ridge which runs to the anterior extremity of the 

 shell. Length, 2-9 ; breadth, 1-85 mm. 



The genus Cithna, being Adamsian, was confusedly framed as 

 Dr. Watsoir'^ has indicated. I have not had the advantagt- of 

 examining authentic specimens, but base based my reference of 

 our species to Cithna on a beautiful figure by Dautzenberg.'' 



The abo\e described is one of the commonest shells on the con- 

 tinental shelf. Besides the present station it is represented in tlie 

 Museum from oft* Port Stephens (Prof. Haswell, IS.SO) ; 41-50 

 fath. off" Cape Three Points (Thetis) ; 54-59 fath. off' Wata Mooli 

 (Thetis) ; 63-75 fath. oft' Port Kembla (Thetis), and 100 fath. off 

 Wollongong (Halligan and Hedley). No Cithna have pre- 

 viously been noticed in Australia. 



3 Hedley— Mem. Austr. Mu3., iv., (>, U»()3. p. 34.5, f. 71. 



* Murclocli — Tranfi. X.Z. Inst., xxsvii., \\)0o., j). 225, pi. viii., F. 10, 17. 



5 Watson -Clmil. Rep., Zool., xv., 1886, j). 519. 



^ Dautzenberg — Result. Camp. Monaco, Fa«. i., ISS'i, pi. ii, f. 8. 



