268 (Ringueberg on the Niagara Shales. 
crintts baiid from one of its most characteristic fossils IIo7>iocri- 
nus parvus. At its inception life was present in great prof usion 
and the lowest portion of the shale is largely made ujd of a mass 
nic remains, mostly fragmentary or distorted, principally 
polyzoa, and disconnected brachiopod valves. But though many 
species and great numbers are represented good specimens ex- 
cept of the more solid forms are rare. Just here a few single 
valves of Orthis lynx were found, representing the last surviv- 
ors of this long-lived species, which flourished during the Tren- 
ton, began to wane in the Clinton and finally ^-ielded to the strug- 
gle for existence here. These first few feet of the shales also 
bear about the only examples of Orthis Jlabella yet found in 
them. Here and there also were colonies of Stepha^iocrinus an- 
gulahis and S. geynmiformis ; the latter of which seems to have 
extended but little higher while its congener gradually decreased 
in numbers, a few occvn*ring part way up the middle third \^\\\\q 
few if any are found above it. The largest examples of Illcenus 
are also to be found here equalling and exceeding the largest 
from the Clinton, though unfortunately almost invariably in the 
shape of disjointed cephalic shields and pygidia, some of them 
measuring eight centimeters across — while a little higher up 
those exceeding three centimeters are scarce. Illce^ius ioxus is 
the form generally found, but, judging from fragmentary evi- 
dence there are one or two others having varietal if not specific 
values. There certainly was a marked decadence of this species, 
especially as regards size, after the close of the Transition, in 
which, and the underlying Clinton, the larger form evidently 
predominated. Calymene also underwent a similar retrogres- 
sion in size after leaving the Niagara Transition. Dalmaniies 
lifmdurus^ Hontalonotus delphinocephahis and Lichas boltoni 
although present do not begin to increase in numbers till to- 
wards the middle of this lower third, Homalouotus not arriving 
at its maximum until the next division is reached; while Lichas 
evidently culminated in the upper half of this one; although it 
is present all through the middle thirds, with a rare fragment 
beyond. Lichenalia concentrica is -at its maximum from the 
very start and gradually with varying fluctuations fades away 
till lost in the upper third. So it is with Streptelasma calyculus 
which however decreases more rapidly in numbers and size; 
