1895. ] NEW YORK ACADEMY OF SCIENCES. 147 
be seen, is short ; the process of development of the eyelobe in 
this family is not a shortening of that protuberance, but a gradual 
withdrawal of it from the margin of the head toward the gla- 
bella ; a Solenopleura then could never have had the eyelobe of 
the form of that of S? Howleyi.* 
Andas regards B. elegans, it is not related to the Ptychoparida, 
notwithstanding a certain resemblance in the pleura. The 
course of its dorsal suture is similar to that of the early forms 
of Paradoxides, and the movable cheek is of the type of the 
cheek of that genus, but its glabella and pleurz separate it both 
from that genus and from Olenellus. It stands apart as one of 
the ancestral types of this ancient fauna. 
BERGERONIA ELEGANS W. D. Matthew MSS., PI. xi., figs. 3 a toe. 
Protolenus elegans, Nat. Hist. Soc. N. Bruns’k Bull. 10., p. 25, 
ae I: 
Eee diplenus elegans, Trans. Roy. Soc. Can., vol. xi., p. 100, pl. 
Xvii., figs. 9a to d. 
Examples of this species taken from the shales, are larger 
than those found in the phosphate nodules; among those col- 
lected from the shales last summer was one having a head-shield 
40 mm. long; this is double the length given in the original 
description of the species; the width at the anterior margin be- 
tween the sutures is about the same (40 mm.), and at the pos- 
terior end 52 mm.; the specimen is a good deal flattened in the 
shale. 
Examples of the thorax show that this species possessed at 
least eight segments ; the thorax has been found partly rolled, 
and also extended at length. 
BERGERONIA ARTICEPHALA PI. x., figs. 5 a and D. 
Agraulos (?) articephalus, Trans. Roy. Soe. Can., vol. iii., p. 
65, pl. vii., figs. 14 a and b. 
Ellipsocephalus articephalus, Trans Roy. Soc. Can., vol. xi., 
p. 104, pl. xvii, figs. 8a and b. 
Numbers of the head shields of this species have been found, 
but all from the same horizon, viz.: sandstones of Assise 3. 
A pygidium occurs in association with the heads of B. arti- 
cephala but not attached; the rachis has three grooves, and the 
same number of grooves appear on the sidelobes. The rarity 
of pygidia in Band } is remarkable, this being the only one found 
among hundreds of heads. 
*In the figure given in “ Fauna of the Olenellus Zone,” this species is represented as 
having a short eyelobe, but this appears to be an error of the engraver, as the description 
indicates a long eyelobe. 
