XVi THE PALEONTOLOGY OF MINNESOTA. 
westward to the headwaters of the Missouri and is said to embrace the lead-bearing lime- 
stones of Wisconsin; it also covers a great extent of country to the east, especially around 
the St. Lawrence river and in New York state. There are 138 species of fossils described; 
these are principally from the lake region of the United States. He discusses at some 
length theexistence of ambulatory appendages in the trilobites, drawing his conclusions 
from his examinations of specimens of Calymene on which he finds certain spots or scars 
which seem to indicate the places of attachment of branchial feet*. The author regards 
the ‘‘systéme magnésifére” as forming an upper member of ‘Murchison’s Silurian, or as 
perhaps constituting a separate formation just above the Silurian. The structure, age 
and formation of the great lake basins are also discussed. 
List OF CASTELNAU’S FOSSILS, PREPARED BY Capt. A. W. VOGDRS. 
Crustacea. 
Asaphus micrurus Green, p. 18, Trenton, N. Y. 
A. limulurus Green, p. 18, pl. Iv, fig. 1, Lockport, N. Y. 
A. cordieri, ”. sp., pl. Iv, fig. 2, p. 18, Lockport, N. Y. 
A. caudatus Brong., p. 19, Trenton, N. Y. 
A. edwardiis, n. sp., p. 19, Trenton, N. Y. 
A.murchisoni, pl. rv, fig. 8, Trenton, N, Y. 
Homalonotus giganteus, n. sp., pl. 10, fig. 1, p. 20, Lockport, N. Y. 
H. herculaneus, n. sp., pl. rv, fig. 5, p. 20, Lockport, N. Y. 
H. atlas, n. sp., pl. 1v, fig. 4, p. 20, Lockport, N. Y. 
Arctinurus, ”. gen., p. 21. 
Arctinurus boltoni Bigsby, pl. mt. fig. 2, p. 21, Lockport, N. Y. 
Calymene bufo Green, pl. 1, figs. 1-4, p. 21, Capon prés du Potomac, Va. 
Odontocephalus, Conrad, p. 238. 
Acantholoma, idem, p. 23, Clarksville, N. Y. 
Aspidolites, idem, p. 24. 
Dicranurus, idem, p. 24. 
Cephalopoda. 
Orthoceras hercules, n. sp., p. 29, Ile. Drummond, 
O. conicum, idem, pl. X, fig. 3, p. 29, Ile. Drummond. 
On propose de substituer 4 ce nom déja employé celui d’O. Castelnau. 
O. filiformis, idem., pl. x, fig. 2, p. 30, Ile Drummond. 
Cyrtoceras markoei, n. sp., pl. 1X, fig. 3, p. 30, Montmorency falls. 
Actinoceras richardsoni ? Stokes, pl. vu, figs. 1-2, Ile Manitouline (lac Huron);idem, pl. vir, flgs. 
2a-b, p 30. 
. blainvillei, n. sp., pl. Vv, fig. 1, p. 31, Ile Manitouline; idem, pl. vim, fig. 1. 
. cordieri, n. sp., pl. Vv, fig 2, p. 31, Ile Manitouline. 
. baudanti, n. sp., pl. v1, fig. 2, p. 31, Ile Drummond. 
. beaumonti, n. sp., pl. v1, fig. 1, p. 32, Ile Drummond. 
- lyonii? Stokes, pl. tx, fig. 4, p. 32, Lac des Bois. 
. dufresnoyi, . sp., pl. viul, fig. 3, p. 32, Tle Drummond. 
A.? deshayesii, pl. vm, fig. 4, p. 32, Baie Verte. 
Huronia obliqua, m sp., pl. 1x, fig. 9, p. 32, Ile Drummond. 
H. stokesi, pl. 1x, fig. 3, p. 33, Schoharie, N. Y. 
Sidemina, Castlenau, p. 33. 
Sidemina infundibuliforme Castln, pl. x, fig. 1, p. 33, [le Manitouline. 
Nelimenia, Castelnau. 
Nelimenia incognita, n. sp., pl. x, fig. 4, p. 33, Moutmorency falls. 
Tentaculites irregularis, n. sp., pl. X, fig. 5, p. 34, Trenton, N. Y. 
T. regularis, n. sp., pl. x, fig. 6, p. 34, Trenton, N. Y. 
Goniatites canadensis, n. sp., pl. xt, fig. 7, p. 34. Montmorency falls. 
rr rrp Pp 
*Late literature on this subject seems to make no reference to this work of Castelnau's. 
