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PROCEEDINGS OF SCIENTIFIC SOCIETIES. 619 
exsert when expanded, and have twelve equal cylindrical tentacles 
surrounding the margin in a single circle, six of them being held hori- 
tally, and the alternating ones erect. This peculiar posture was 
the principal difference observed between these animals and those of. 
Porites, when compared side by side 
From the disagreement in the character of the animals of Millepora 
and Pocillipora, in connection with great differences in the corals, it 
It is probable that Favosites, and many 
other extinct tabulated genera belong with Pocillipora, while Helio- 
lites, etc., may go with Millepora. Therefore we must regard the Tab- 
ulate structure as a character of secondary importance and the arti- 
ficial group of Tabulata must be dismembered. 
“On the Coal Measures of Illinois, with a vertical section of the 
8 SB n the prosecution of 
the Geological Survey of Illinois, it seemed desirable to identify our 
i ch as the Illi- 
nois and Kentucky coal-field was known to belong to the same basin; 
and with this end in view, a general examination of our coal-measures 
the main coal-seams occupied in the Ilinois section, especially those 
recognized as the equivalents of Nos. 5-9 and 11, of the Kentucky 
Section, were erroneous, and that if that section was correct, no paral- 
coal-seams of the two States. 
ately above the conglomerate. This 
‘Sta 
tween the two. Hence we were led 
section in Kentucky, a single 
