51 - 
S.A* XAT , YOI.. XV. 
m.mwii 2 7-ni. 193-k By Bernard Cotton and Y . K. Godfrey. 
gradually thins out about the middle ol each side; perforation 
ah" surrounded b\ a callus. Length 24, breadth 12. height ; 
•nr... .Not common; beach, Mac! )onncll tiny. Robe, Port W'il- 
lunga, Pondolowie ibo , Srealcs Bay, Si. Francis Island. Alsu 
Western Australia—beach, Albany, S allingup, Kllen bn ok. Bun- 
hr y, Rottncst, and dredged, to 35 fathoms. (Type Iocalitv — 
hh' ders, Victoria). Of many examples regarded as obforya 
Minke, from Western Australia, the largest measures 22.1 x 13.5 
x L mm., th.e slit 5 mm. long, 5.2 breadth; hole almost exactly 
central. 
Macrochisma Swainspn 1840 Macraschh in a of most 
autnors). / issiirellidac with an oblong shell not at all cov ered 
b} the mantle, and much shorter than the long lleshv foot, its 
?\xx near the posterior margin, wholly removed bv a large sub- 
tnxngular fissure the wider end of which is verv close to the 
P ( 'w'fior end ol the shell. I he shell is situated on the front 
part ot the body, the mantle extended a little in front of it. 
lunacies long, subulate, the eyes on slight swellings at their outer 
Kj ipodial ridge wholly obsolete. Anal tube rather long, 
directed backward. I vpc—51/. liiaiula Sowerby. Distribution 
u! genus—Iado-Pacific and from Tasmania to Japan. The more 
obvious characters arc the large fissure close to the hinder end 
of the shell, margined inside by an entire narrow callus, and the 
p< >terior position of the vertex. 
M. products A. Adams 1850. ’' The Prolonged Machroch- 
isma. PI. 1, jig. 11. Narrowly oblong, back elevated, convex; 
Mite, variegated with pale brown or pink; obsolete]}' decussated 
vrnh elevated lines and concentric striae; anteriorly narrow, pro¬ 
duced, with plam.ilale sides; posterior extremity rounded, elevated; 
margin deeply sinuated; fissure ven long, triangular, dilated pos¬ 
teriorly. Length 2<\ breadth 10, height 6.5 mm. Backstairs 
Passage, Xormanville, V ankalilla Bav, American River. Kdith- 
btugh, Hardwicke Bav, Pondolowie Bav. Boards Bay. beach and 
dredged to 20 fathoms, uncommon. Also Western Australia — 
king (ieorge Sound, Albany, Rottnest, I [opetoun, Bunburv, (icr- 
tikiton, mi beach, uncommon. (Tvpe locality—Port Lincoln), 
from .1/. las maniac Sowerby, this species is narrower, more 
vertical sides, fissure narrower and longer, resulting in a corres- 
p« tiding projecting curve on the peripherx of the aperture; so.lp- 
Uwe liner. 
M. tasmaniae Sowerbv 1866 (— M. tasmanica Terns-m- 
II nods 1875. afterwards chajiged to M. vccldb. Yenison-W oods 
bS76). Oblong, length nearly double the Lr-eadlh, elevated, 
abitude one-fourth to one-third the length; latei. l margins some- 
Waat convex; whitish, obscure.lv emmem • :,xdl\ clouded with 
