ANTICOSTI ISLAND FAUNAS. 
27 
This is the earliest known appearance of this genus and since 
it is already a fully developed Chonetes it follows that it originated 
still earlier in the Ordovician. From its decided resemblance 
to Brachyprion leda it is extremely probable that both came from 
the same stock, viz. ; a small leptaenoid ? with a narrow muscle 
scar, fine plications, and a single central plication of large size. 
In the Anticosti measures Leptaena? nitens answers to this 
description. 
C, primigenius is smaller than the European C. striatella 
and more finely striate; it is larger than C. cornutus from the 
New York Clinton; it is about the same size and shape as C. 
tenuistriatus from the Arisaig Silurian, but that shell does not 
appear to have the prominent mid striation and is less finely 
striate. 
Horizon and Locality. Ordovician and Silurian. The species 
first appears on the north side of Anticosti in zone 3 of the Charle- 
ton formation. Its next appearance is at Ellis bay in the Ellis 
Bay formation and again at Wreck beach in the Gun River 
formation. A single specimen was collected at the Jumpers 
in zone 9 of the Jupiter River formation. 
The holotypes and paratypes are in Peabody Museum. 
Superfamily, Pentamerana Schuchert. 
Genus , Virgiana new genus. 
(Virgie, proper name.) 
The generic name of Clorinda was proposed by Barrande 
for shells of which casts of the interior showed a series of strong 
ridges radiating from the umbonal ridge of the pedicle valve, 
these being produced by the vascular or ovarian sinuses. He 
stated that his two species were pentameroids not unlike C. 
linguifera . For this group Hall and Clarke proposed the generic 
name of Barrandella, the genus including .shells which externally 
are moderately transverse, ventral valve the larger, moderately 
galeatiform, with a sinus on the ventral valve and a fold on the 
dorsal. In the Becsie River formation of the Anticosti section 
occurs the shell described by Billings as Peniamerus barrandei 
which in its young stages has all the characters of a true Clorin- 
