The Family BoJiemillidce. — Beecker 
361 
that the " genal spine" in question was apparently about 
one-half of the rim of the displaced pygidium with the doub- 
lure, and had no organic connection with the cephalon. 
Another character shown in the principal specimen and over- 
looked in the original description was the presence of a frag- 
mentary facetted area at each side of the fifth annulation, or 
at the base of the cephalon, indicating that originall}- the 
visual area extended the entire length of the glabella. The 
finished margin of the eye, as figured by Barrande, is incor- 
rectly represented as complete, whereas the posterior edge is 
an irregular and broken line. 
This additional information, together with the fact that 
there are six free axial segments, indicates the proper reference 
of this species. dEglina, Barrande, meets all the requirements 
in having eyes extending the whole length of the cephalon, 
six free thoracic segments, and a pygidium with an entire 
margin and striated doublure. It is important to note that 
the locality furnishing the specimens of B. stupendn, Sancta 
Benigna, Bohemia, is the chief source, also, of most of the 
species of JEglina. The trilobites from this locality are often 
compressed and broken, and occur as easts in a soft carbon- 
aceous shale, so that the distinction between fossil and matrix 
is not always clearly shown. 
I + 3 
Figures 1, 'l, :s. JEglina stupenda Barr. sp. (Figure l, after Barrande.) 
Figure 1 of the accompanying cut is after Barrande, with 
the restored portions represented by dotted lines. Figure 2 is 
the same, showing the additional facetted areas at the base of 
the cephalon. Th<> outlines of the eyes, the pleura of the 
thorax, and the form of the displaced pygidium are supplied. 
