209 



Black Island, by J. B. Tyrrell in 1889 and by D. B. Dowling and L. M. 

 Lambe in 1890; at Big Sturgeon Island by Mr. Dowling and Mr. Lambe 

 in 1890 ; and at the mouth of the Fisher River by Mr. Dowling in 1891. 



Although part of the test is preserved on some of the specimens from 

 these localities, it is invariably so much worn or weathered as to shew- 

 no trace of the "longitudinal, undulated, thread-like lines" which sug- 

 gested to Hall the specific name temdfilum. The surface markings, how- 

 ever, are rarely preserved in specimens of 0. Bigsbyi from the Black. 

 River or Trenton limestones of the provinces of Ontario or Quebec. 



The siphuncles of the specimens from Lake Winnipeg and the Red 

 River valley, which are here referred to A. Bigsbyi, are quite different in 

 their contour to those of A. Richardsonii. In the former the siphuncle 

 consists of prominent annular ridges, with deeply and obliquely excavated 

 grooves between them, and the latter of a single series of large anchylosed 

 nummuloidal discs, with rounded edges. A portion of a siphuncle, from' 

 Snake Island, Lake Winnipeg, which is crushed almost flat but somewhat 

 obliquely, and which may represent an extreme form of A. Bigsbyi, has 

 the annular ridges low and rounded and the groovers or constrictions 

 between them unusually broad and shallow. The longitudinal section of 

 a specimen from Little Black Island represented on Plate 10, fig. 2,, 

 of the ninth volume of Transactions of the Royal Society of Canada, 

 " shews the opening of the large foramen directly into the endosiphon 

 posteriorly, and some of the lateral canals or tubuli, which radiate first 

 outward and then outward and forward, from the endosiphon. Not a 

 vestige of the chamber of habitation of this species, nor of that of A. 

 Richardsoni, has yet been discovered." 



The types of Actinoceras Bigsbyi are from Thessalon Island, Lake 

 Huron, where they were collected by Dr. Bigsby in 1820. In the 

 "Geology of Canada" (1863), specimens which were identified by E.. 

 Billings with A. Bigsbyi (under the name Orthoceras Bigsbii) are recorded 

 as occurring, in Ontario, on Campement d'Ours Island, on the Palladeau, 

 Manitoulin and Lacloche Islands and on Snake Island, in Lake Huron, — 

 at Loughborough, Dickson's Mills, near Pakenham and Cornwall ; in 

 Quebec,at Point Claire (on the island of Montreal,) Montreal, St. Ambroise 

 and Lake St. John. The specimens from Montreal are from the Trenton 

 limestone, but all the others from the localities just cited, in the provinces 

 of Ontario and Quebec, are from the Black River limestone. 



Actinoceras Allumettense, Billings. (Sp.) 



Orthoceras AUuviettense, Billings 1857. Geol. Surv. Canada, Rep. Progr. 



1853-56, p. 331. 



,, I, Barrande 1870. Syst. Silur. de Boherae, vol. II., pi. 



436, figs. 6-9. 



Barrande 1874. Ibid, texte III, p. 729. 



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