ANTICOSTI ISLAND FAUNAS* 
31 
Protozeuga anticostiana new species. 
(Plate I, figures 8-10). 
Shell very small, longitudinally pentagonal; anterior angles 
gently rounded, front straight; cardinal angles more abruptly 
rounded than anterior; cardinal slopes straight, meeting at about 
90 degrees; an average specimen is 5 mm. long, 4 mm. wide, 
depth of both valves 2.25 mm., surface smooth; shell structure 
punctate as shown by etching with hydrochloric acid. 
Ventral valve highly convex, deepest about one-third the 
length, keeled at the beak, toward the middle of the valve the 
keel widens out to a flat-topped fold which at the anterior margin 
is replaced by a sulcus; slopes to the lateral margins quite steep 
and at the cardinal angles the surface is slightly concave. Beak 
small, narrow, truncated by a small foramen, incurved and over- 
arching the hinge line; no area. 
Dorsal valve convex posteriorly and laterally, slightly de- 
pressed or concave just anterior to the hinge and divided into 
two lobes by a wide uniformly concave sulcus. 
This shell closely resembles Protozeuga mawii (Davidson), 
but is slightly larger and proportionately wider. It occurs in 
much older strata and, while its brachial apparatus has not been 
demonstrated, its strong resemblance to the above species shows 
it to be congeneric. 
Horizon and Locality. Ordovician; English Head (2-3), 
English head; Charleton (2-3), English bay and White cliff of 
the north shore. 
The holotype and paratypes are in Peabody Museum. 
Superfamily, Spiriferacea Waagen. 
Family, Atrypidae Gill. 
Subfamily , Lissatrypinae new subfamily. 
Smooth atrypoids with the external aspect of Nucleospira . 
Genus , Lissatrypa new genus. 
(Lissos, smooth; atrypa). 
In 1866 Billings described from Gull cape (Wreck beach), 
