35° -^- Winchell on the 'laconic Question. 
4. Constitutioti. In the first enunciation of the system, Dr. 
Emmons was not fully persuaded of the order of superposition 
of the strata embraced in the Taconic belt. Leaving that deter- 
mination to the future, he described them in geographical order 
from the west. As the general dip w^as easterly, this order 
would be ascending, imless the whole system had been subjected 
to an overturn. The order was as follows: 
Taconic slate, sparry limestone, magnesian slate, Stockbridge 
limestone, granular quartz. 
In the first volume on the Agriculture of New York, the 
preface to which is dated December 30, 1S46, Dr. Emmons de- 
scribes the members of the Taconic system in the following 
oi'der : 
Black slate, ^vith two species of trilobites. Not here certainly re- 
garded as belonging to the Taconic. 
Taconic slate Avith its subordinate beds, with various markings re- 
ferred to Nereites. Cited from Brunswick, Rensselaer county. 
Sparry limestone. 
Magnesian slate. (Talcose slates of 1856.) 
Stockbridge limestone. 
Brown sandstone or granvilar quartz. 
5. Palceontologic characters. In the original characteriza- 
tion of the system, it was supposed to be destitute of fossils. 
This was made one of the points of distinction from the rocks 
of the Champlain Division. In the agricultural report, how- 
ever, the author, besides describing and figuring two genera of 
trilobites — At ops triliiteatus and Elliptocephala asaphoides 
(now known as Conocephalus and 0/e«^//?^5') — from the Black 
slate, described and figured eleven species of Nereites and two 
fucoids; also one crushed tube supposed to be that of an annelid. 
Subsequently, many more species have been discovered in the 
rocks embraced by Dr. Emmons in the Taconic system. 
6. Original grounds of the Taconic system. ( i ). Litho- 
logical: Compared with the palaeozoic rocks, they are not the 
same, nor the same in a metamorphic state. Nor do the differ- 
ent lithological divisions occur in the same order as the divisions 
of the Champlain group from which they might seem to be 
derived by alteration. Further, they are distinguished by the 
presence of ha^matitic masses, while the iron of the Silurian is 
argfillaceous or oolitic. The black oxide of mang-anese is another 
