936 TRANS. OF THE ACAD. OF SCIENCE. 
bigny to separate Reteporina, or minute lines of pores on the 
midrib would a ae him to establish the ore of Fenes- 
trellina. The remarks may be applied t Kera- 
tophytes of Schlotheim, the Polypora of ‘Me Coy, and the 
ocladia of King. If the Keratophytes is to be separated 
because it has more than two serial lines of pores without me- 
ribs, we see no good and sufficient reason why our sub- 
genus may not be established on the characters which we have 
indicated above. It is certainly a departure from the origi- 
nal type of Fenestella as limited by “bo Orbigny, as well as 4 
departure from the broader limit given by King, in the ab- 
sence of median ridges between the at series of pores. 
We have another specimen from Warsaw, Illinois, which 
seems to be larger and somewhat differently bien 
this the cells are large and tuberculated in the tw 
prominently indenting the sides of the fenestrule, but the 
number of pores to the fenestrules could not be determined 
because of the ra ateat of the dissepiments ; it seems to be 
a larger and be eserved species of this subgenus. : 
Taality ee. ens of St. Louis Limestone, St. Louis. 
_ Frenestetnia pirumosa. (Prout.) 
Ss lieilllog Sobting 4 Vobd, — funnel-shaped frond, about three inch 
es —— one and a ; bifurcations frequent, at from one f 
not slender, beautifully striate on reverse; = 
—— rately lar, , slightly seve lang into three OF or ) 
low tubercles to Bap pore waved linear where not worn. T hese 
tubercles are less than their diameter ie part sometimes ope some- 
‘ i with el 
Interstices thick, round: short, peeling? at their sommes with the. 
pon se kd fbn te suboval form to the fe 
: oer oy ot ta twice as] 
large, indenting the margin of the fene nestrule, three t 
att 
to give greater 
ere av alco, the 
