Monthly MScroscopican 
Juurnal, Oct. 1, la69. J 
in Carboniferous Limestone. 
183 
With the above were also associated five genera of land and 
fresh-water shells. 
Extending my observations into North Wales and the north of 
England, I again found the same general conditions prevail, and 
that, more or less abundantly, the lead veins yielded organic remains, 
some of them at great depths. 
In the Fallowfield mines and the Silver-band mines, two very 
minute seeds of the Flemingites gracilis, Carr., were found ; and 
since then I have discovered that horizontal beds of the coal- 
measures are almost wholly composed of them ; and I infer that 
the Fallowfield mine received its minerals and the other contents of 
the veins subsequently to the coal period. 
In many of the veins in districts wide apart I discovered many 
of those remarkable bodies called Conodonts by Pander. They had 
been found by the latter in Silurian beds in Eussia, who, consider- 
ing them to be the minute teeth of fish, created fifty-six species for 
their reception. Several kinds have been found by Dr. Harley in 
the Silurian bone-bed of Ludlow, who has suggested that they 
belong to Crustacea. They have also lately been noticed by 
Professor Owen, in a note, in ' Siluria,' p. 544, who also points out 
the improbability of their being alhed to fish. He thinks the 
simpler forms not unlike the pygidum or tail of minute Ento- 
mostraca, but that against this view was the fact that no 
Entomostraca were found with them ; and he then states the 
probability of their having been united to the soft perishable 
bodies of naked mollusks or annelids. I found a great variety 
of curious forms, not only in the lead veins, but also in stratified 
beds of Carboniferous Limestone, so that their range in the geo- 
logical series has been greatly extended. I stated that though 
I might agree with the view of Professor Owen, it was not correct 
to say that they were not found with Entomostraca ; for though 
this might not be the case in Silurian strata, yet in the Carboni- 
ferous Limestone the beds in which they were found were some of 
them in great part made up of this crustacean. The Conodonts 
were usually about a line in length, the simpler ones being not 
unlike that of a minute conical fish-tooth. I have about forty 
varieties, some of the forms of which are not unlike fish-jaws, 
whilst others are almost too eccentric and peculiar for separate 
description. 
The Entomostraca, though not individually numerous, were 
present in almost every mineral vein I have examined, consisting 
of about twenty-nine species, most of which were new. They were 
included in the genera Bairdia, Beyrichia, Gythere, Gytherella, 
Kirkhya, and Moorea, the genus Cythere having about seventeen 
species. 
