41 
S.:.. NAT., VOL. XV. 
mv.xii 27tit, 1934. By Bernard C. Cotton and F k. Godfrey. 
SOU1H AUSTRALIAN SHELLS. 
('Lieluding descriptions oi New Genera and Species). 
(Z>\ Bern \rd C. Cotton 2c I. K. Godfrey). 
PART X. 
FISSURELLIDAE. 
Conical, Jimpet-shaned; with a hole in the centre, or will 
t! e front margin slit or notched; protoconch spiral, turned towards 
the h.indcr part, where it forms a short and complete excentiic 
spire, a!wa\ s in the voting and mostly in the adult; muscular 
impression horseshoe-shaped, open in front. No operculum- 
Distribution—World-wide, but mostly in warm seas, from low 
water to moderate depths. Fossil—Carboniferous. Animal con¬ 
ic.i or semi-oval; mantle folded in front, forming a tubular pro- 
am, which occupies a slit in the margin or near the summit at 
that end of the shell, or else a hole in the crown; head prominent, 
with a short muzzle; tentacles tapering; eyes on short tubercles 
one at the outer base of each tentacle; gills paired, one on each 
side of the back, their free ends extending to the neck; foot 
thick, studded above or covered entirely with papillae; veir 
interior, placed in the middle between the gill plumes. Scxe-* 
distinct. None of the FissurcUidae can properly be called littonc 
ait hough some are occasional! v found under stones at low water 
mark. They arc plant feeders. Outer layer of shell laminated, 
middie one cellular, inner nacreous. Protoconch spiral, although 
me adult shell assumes a conic form; in some genera there is a 
mdimentarv spire in the young state, which disappears in the 
course of growth. 
Scutus Mont fort 1810 (= Parnwphorns Blainville 1817: 
= Scutum of some others). Scutum, a large quadrangular shield- 
Obionv, depressed, protoconch directed backward; no anal groove 
or slit, but the front margin more or less truncated and sinuous; 
surface without radiating sculpture; anterior ends ot the muscle- 
scar converging but not hooked inward toward the apex, lype— 
Scutus antipodes Momfort: - S. ambiyuus Chemnitz. Shell 
|artly concealed by the mantle; animal black or blotched with 
black, snout and tentacles long; epipodial row of papillae present. 
Thev are shy and avoid the light; they are found under bould¬ 
ers between tide marks. This Indo-Pacific genus represents the* 
more primitive form of the family. The lack of radiating sculp¬ 
ture. smooth edge of the shell, and differently formed muscle-scar 
afford amply sufficient characters for the separation of the genus 
from K mar An ul a. 
o 
