NOVA SCOTIAN GEOLOGY—HONEYMAN. 19 
lobe. It partially remains on the right. It is wanting, having been 
broken off the apex. The whole trilobite, if proportioned like the 
Isotelus gigas must have been 1 foot 3 inches in length. There 
accompanies, the cheek of a smaller individual, nearly resem- 
bling that of Asaphus gigas. The fragment of rock in which it 
4s imbedded is heavy in proportion to its size, in consequence of 
the iron which it contains. It is Magnetite. Dr. J. B. Gilpin, to 
whose kindness I am indebted for the specimen, informs: me that 
it was found in the Iron Mines of Clements, Annapolis Co.. At 
his suggestion I have named it after Mrs. Laura Ditmars, who 
secured it from the collection. This is by far the largest member 
of the trilobite family that has yet been discovered in Nova 
Scotia. It is one of the Anahkim of the Silurian period. I shall 
quote authorities to show the distribution and range in time of 
the Fumily Asaphidae. 
ENGLAND.—Murchison. 
“The genera Trinucleus, Asaphus and Ogygia, are never de- 
tected, even in the lowest part, of the Wenlock group, therefore, 
being essentially characteristic of the Lower Silurian rocks,” 
—Siluria, 1872, page 114. 
Salter. 
Asaphidae, a large unwieldy group of great trilobites, which 
are characteristic strictly of Lower Silurian. rocks. The excep- 
tions to this geological position are very rare. Except Illenus: 
it does not rise out of the Lower Silurian, and it is very rare 
even in Llandovery or Middle Silurian rocks. Niobe, Prilo- 
cephalus, Asaphus, Ogygia and their swb-generw; one or other of 
these genera are characteristic of every locality where Tremadoc,, 
Llandeilo, or Caradoc strata are found. 
Asaphus or Isotelus is the largest, excepting of course Para-. 
doxides, among the Olenidae. Ramsay’s Geology of North: 
Wales, page 310. 
BouEmMiA.—Barrande. 
Trilobites. 
“Fannes Siluriennes—Distribution verticale des Trilobites em 
Boheme. 4 
2 
