Lower and Middle Taconic. — Marcou. 363 
says : "the name, from its similarity, is no doubt objectionable, 
but I am disposed to retain it for the present." ("American 
Geology," p. 114, Albany, 1855). So, until an imderstanding 
is reached among palaeontologists to replace Emmons' original 
name by another which shall be acceptable to the memory' 
and respect due to the discoverer, it is best to use Emmons 
name of ElliptocepJialus as he expressed it. 
In the case of the trilobite of Kunda and Strietberg near 
Reval, it is not an ElliptocepJialus ( Olenellus) of the Georgia 
typical io\'m.Elliptocephahis{ Olenellits)t/wmpsoni,on account 
of its pygidium totally different, its head remarkably large 
and elongated ; and finally the thorax also presents great 
difi'erences in the lobes, and in the existence in the middle of 
the thorax of spines (like the genus Holmia), one of which 
on the eighth articulation, is a spade-like form or telson, tres- 
passing over the pygidium, and having a length as great as 
the elongated head. In reality this trilobite possesses generic 
differences and constitutes a new sub-genus, closely allied to 
Paradoxides, and in which may be included Mesonacis ver- 
montana and Olenoides typicalis, the latter being an extreme 
degenerate form of the type. I propose to call it Schmidtia^ 
in honor of professor F. Schmidt. 
I shall call the group of strata found at the two places in 
the vicinit}' of Reval, Esthonian formationov Schmidtia zone; 
a new group not yet found anywhere else, so far as fossil 
animals are concerned, and which is placed at the top or upper- 
most part of the Lower Taconic or Infra-Primordial. It cor- 
responds stratigraphically with the Eophyton sandstone of 
Sweden, the "Sparagmite stage" of Norway, and the beds 
below division m of the Newfoundland column of lower 
palaeozoic strata, in Conception bay. 
As a resume, of the Infra-Primordial, the first great group 
or Newfoundlandian formation contains, so far, only one cer- 
tain species of fossil, the Aspidella terranovica with indica- 
tions of remains called Arenicolites, fucoides and ArchcGOcy- 
atJius^ more or less problematic ; and the second great group 
or Esthonian formation contains eleven species, making for 
the whole of the Infra-Primordial fauna only twelve fossils. 
III. Scandinavian fokmation. — Sweden and Norway. — We 
come now to the Middle Taconic, the Magnesian and Black 
slates (rt and e) of Emmons, tho Regio n Olenorum^=^A of 
