288 scutus. 



muscle-scar converging but not hooked inward toward the apex, as 

 there are in Subemarginula-\- Tugalia. 



The shell is partly concealed by the mantle : animal black or 

 blotched with black, snout and tentacles long ; epipodial row of 

 papilla? present; formula of dentition x (1) 4-1-4 (1) x. 



This Indo-Pacific genus represents the more primitive form of the 

 subfamily. The lack of radiating sculpture, smooth edge of the 

 shell, and differently formed muscle-scar afford amply sufficient 

 characters for the separation of the genus from Emarginula and 

 Subemarginula. 



Mr. E. A. Smith has thoroughly revised this genus in an excellent 

 paper in the Quarterly Journal of Conchology, ii, p. 250, 1879. The 

 positions there taken are undoubtedly correct, and I have been 

 guided by them in the following account. 



S. anatinls Donovan. PI. 40, figs. 1, 2, 3. 



Shell oblong, depressed, sides parallel or converging in front ; 

 ends rounded, the front end somewhat sinuous, not squarely trun- 

 cated ; surface concentrically striated, not obliquely corrugated ; 

 apex at about the posterior fourth of the length. Color buff or 

 yellowish-brown. Inside white, usually with some purplish or 

 orange stains ; muscle-scar distinct, rugose ; there are usually some 

 punctures at and behind the apex of the cavity. An average speci- 

 imen measures, length 76, breadth 36, alt. 10 mill. 



Bass's Straits, Port Jackson and Sidney, Eastern and Southeastern 

 Australia; broad variety from Western and Southwestern coasts of 

 Australia. 



Typical form. Shell elongate, narrow. 



Patella anatina Do>\ in Rees' Encyclopedia, 1820, v, nat. hist, 

 plates Conchol., t. 16. — Scutus anatinus E. A. Smith, Journ. of 

 Conchol. ii, 1879, p. 257. — Parmophorus elongatus Blainv., Bull. 

 Sci. Soc. Philoni. 1817, p. 25; Diet. Sci. Nat. xxxvii, p. 557: 

 Malacol. t. 48, f. 2, 2a. — Emarginula elongate Sowb., Genera, f. 1. — 

 Scutus elongatus A. Ad. in Sowerby's Thes. iii, t. 248, f. 1, 2 ; Conch. 

 Icon, xvii, t. 1, f. la-b. — S. unguis A. Ad. in part, (not Linn.) P. 

 Z. S. 1851, p. 221. — Parmophorus australis Lam., Ciiemx., Reeve 

 (Conch. Syst. t. 139, f 2-3),— Hogg, Trans. Microscop. Soc. 1868, 

 xvi, t. 12, f. 57 (dentition). — P. convexus Q. & G., Voy. Astrol. iii, 

 p. 322, t. 69, f. 5-16. 



