. 
THE FAUNA OF THE ST. JOHN GROUP. 101 
Glabella—The fourth furrow is at this stage somewhat less than three-fifths from the 
front of the dome. 
The occipital ring is proportionately much narrower than in 10.9 mm. stage of this 
variety, the width being less than one-third of the length. 
The posterior margin at this stage is about twice as wide proportionately as in the 
preceding. 
The length of the ocular lobe on the contrary, is reduced. 
Sculpture —At this stage the concentric raised lines disappear from the higher part of 
the dome, but are still distinct for about half of the distance up its slope. In other respects 
the sculpture corresponds with that of the earlier stages. 
23.7 MILLIMETRES. — Glabella.—The fourth furrow is somewhat more than three- 
fifths (%) from the front of the dome. 
Occipital ring. —The width is scarcely more than a quarter of the length. 
Fixed cheek.—TVhe ocular lobe is somewhat smaller than in the last described stage. 
The development of the glabella in this form appears to take place more rapidly than 
in either of the preceding (efeminicus and suricoides). Even the smallest has a fully rounded 
and raised dome, and at so early astage as 15.4 mm.; the fourth furrow is found to be about 
three-fifths from the front of the dome. 
Locality —Found at Portland, N.B., in Division 1c. with the two preceding forms, 
Var. Mauicitus ( Fig. 13). 
This form presents some marked differences from P. efeminicus. 
The occipital ring is very wide, being nearly half as wide as it is long. It is about one- 
fifth of the length of the cephalic shield. 
Fixed cheek, is very wide and strongly arched upward at the outer side, a shallow 
depression crosses it lengthwise, and it is strongly deflected downward in front and behind. 
This is the only well-grown individual found in the St. John Cambrian rocks in which 
the width of the fixed cheek exceeds that of the glabella. The eyelobe is very long and 
prominently elevated at the posterior end; it is a fifth longer than that of P. eteminicus—of 
a corresponding size. 
Seulpture—The surface is not sufficiently well preserved to show the markings, except 
a part of the concentric raised lines around the front of the glabella, and these appear to be 
similar to those of the three forms already described. 
The anterior margin is deficient in this specimen, but supposing it to resemble that of 
P. eteminicus, the following measurement will represent the cephalic shield :— 
















| Suture Measurement. Axial Diameter. Transverse Diameter. 
: | Glabella. Basal. Middle. | Anterior. 
Selee!lSalHuSiia ies | 
Length. Be] CS) 621 cs |£s j 2.5 | | | Distortion. 
S#iso| S82) os || 2a | -|oP|eela Pil eel SAIS 
@S|5elaS| 8288 |es/as| Sles EE 25/4] = |28| à 
Ba /OR| | Og1S "| &3/se| 8) <S|SË|Rs)Ss| 2 58) 2 
An |gn| À es | /ES| S| es] © 
| Ex | AT | & |<#| S 
SS À a | ee ee ee nA! 
| RAiru) : 
21°8 millimetres|12 |-54 |?-24 |-24 |/-18 1:09 [15 [53 (2-06 ||-37 |*43 |-50 |-47 (2:39 |-65 | o 








Locality—Portland, N.B. In Division 1 c. 
