FAUNA OF THE ST. JOHN GROUP. 273 
The posterior part of the flat area is very wide, and the spine long and regularly 
curved. The margin of the flat area is not well defined. 
Sculpture. —The upper side of the anterior marginal fold is marked at the genal angle by 
from twenty-five to thirty-five (25-35) fine, raised lines (most numerous in the adult) : 
these lines are more irregular and anastomose more frequently than in the other species. 
Half-way down the genal spine these lines are reduced in number to about twenty (20). 
The posterior marginal fold has two or three (2-3) fine lines crowded along the outer margin, 
and at the genal angle about eight (8) broken lines running around outside the outer 
corner of the flat area. The flat area is smooth with an undulated surface, and has about 
three sfriæ (not raised lines) crowded along the edge of the ocular suture. 
Length, from three to three and a half inches. 
Found at Portland in Division 1e. 
This species in the numerous lines on the anterior margin is allied to P. quacoensis and 
P. pontificalis, in size it is nearer the latter, but in the great width of the posterior part of 
the flat area, it resembles the former. 
No. 6. (Fig. 4). 
Distinguished from the others by its small size and granulated flat area. 
The genal spine is nearly one and a half (13) times as long as the posterior margin, and 
is strengthened by a keel which runs lengthwise along its surface about one-third from 
the outer margin: the spine is not much arched and is much narrower than the anterior 
marginal fold. The narrow anterior part of the flat area is about two-thirds (2) of the 
width of the anterior marginal fold. 
Sculpture—The anterior marginal fold has about nine (9) strong, raised lines on the under 
surface (but the upper surface is nearly smooth). The genal spine has on the upper side about 
four raised lines visible only with a lens; these lines are between the keel and the iñner 
margin of the spine. No raised lines were detected on the posterior marginal fold, but its 
surface appears minutely granular under the lens. The surface of the flat area is granu- 
lated, the markings being just visible to the naked eye, and largest at the outer angle. 
Length, nearly three-quarters of an inch. 
Found at Portland, N.B., in Division 1e. 
This cheek, in its markings and its small size, appears to come nearer to P. acadica 
than to any other species known in the St. John Group. 
THORACIC SEGMENTS. 
The material in my possession representing this part of the body of the Saint John 
Paradoxides (the thorax) are too fragmentary to enable me to obtain any satisfactory 
results from their study. There were however one or more species in which some of the 
lateral appendages of the thorax were extravagantly prolonged. 
PYGIDIA. 
There are three distinct types of pygidia found with the Paradoxides that occur at 
Saint John. One of these groups of forms may be described, as orbicular-ovate (A), another 
as orbicular-obcordate (B), and the third as obcordate-lanceolate (C). 
Sec. IV., 1883. 35. 
