Fauna of the Morrow Group 
127 
P. ehrenbergi^ the type species. The second, of minor import- 
ance, is in regard to the shape of the zoarium. Waagen and 
Pichl insist upon the funnel-shaped form of the colony although 
King defines it as “consisting of infundibuliform, folded, perfor- 
ated fronds or foliaceous expansions.’' The fragment at hand 
may possibly be a portion of a funnel-shaped colony though if 
so, it was not nearly so cornucopia-like as the type species or as 
the best preserved of the Salt Range Phylloporas, but it is more 
likely a part of a “foliaceous expansion.” 
Horizon and locality. Hale formation: East Mountain, Fay- 
etteville, Arkansas (Station 136). 
Phyllopora cribrosa n. sp. 
Plate VI, figures 5, 5a. 
Description. Zoarium a foliar expansion composed of sinuous 
branches united at regular intervals by poriferous dissepiments 
into a rhythmically perforated plate. Branches regularly 
rounded, a little more strongly convex on the reverse than on the 
obverse face, 0.5 to 0.7 mm. wide on the former, 0.6 to 1.0 mm. 
in width on the latter side, about 6 occurring in a centimeter; 
small nodiferous protuberances are scattered irregularly over the 
reverse face of the frond. Dissepiments the same shape as the 
branches and nearly or quite as strong, depressed somewhat 
below either face of the zoarium and expanded terminally ; situ- 
ated at right angles to the general trend of the branches. Fenes- 
trules regularly hexagonal in outline with rounded corners, 1.2 
to 1.3 by 1.0 to 1.2 mm. in size, on the reverse; oval in shape 
on the obverse face where they are somewhat narrower; 51/2 
occur in 1 cm. Zooecia in 4 to 6 slightly irregular ranges on the 
branches and with 5 or 6 apertures on each dissepiment; the 
apertures not confined to the obverse face of the branches and 
dissepiments but encroaching laterally upon their regularly 
curved sides and with prominent peristomes thus giving the 
fenestrules a scalloped outline in the sections parallel and adja- 
cent to the poriferous side of the zoarium ; apertures circular, 2 or 
more diameters apart in the rows, 17 or 18 occurring in 5 mm. 
Horizon and locality. Morrow formation: near Ft. Gibson, 
Oklahoma (Station 296). 
