165 



rounded anterior margin than in L. lowensis, L. rectilateralis, or L. 

 Cincinnatiensis, Hall and Whitfield." 



On the other hand, M. Friedrich Schmidt, of St. Petersburg, who - 

 visited the Museum of the Survey on the second and third of October, 

 1891, and carefully examined the specimens identified by E. Billings, 

 expressed the opinion (which the writer took down in writing, at the 

 time, from his dictation) that the Anticosti specimens labelled Lingula 

 quadrata, Eichwald, are exactly similar to Eichwald's types, and that two 

 specimens from the Trenton limestone near Montreal that are similarly 

 labelled, may be correctly named. 



Lingula elongata. Hall. 



Linyula elongata, Hall 1847. Pal. K. York, vol. I, p. 97, pi. 30 



fig. 5. 

 BiUings 1863. Geol. Canada, p. 161, fig. 135. 



Inmost Island, Kin wow Bay, Lake Winnipeg, T. C. Weston, 1884 : 

 a flat piece of limestone with one surfa,ce strewn with numerous valves of 

 a small Lingula, which agrees^very well with Hall's description and figure 

 ■of L. elongata, but which is almost intermediate in size between that 

 species and L. riciniformis. Two of the most perfect of these valves 

 measure respectively, the one lO'S mm. in length by 6 mm. in breadth, 

 and the other 8-5 mm. by 5-5. All of them shew the "narrow depressed 

 line " which " extends along the length of the shell, from the beak, more 

 thnn half way to the base," which constitutes part of the original descrip- 

 tion of L. elongata: According to Messrs. Winchell and Schuchert,* L. 

 elongata. Hall, differs in being twice the size of L. riciniformis, but if 

 this is the only difference between these two forms, the former could very 

 well be the adult state of the latter, though Hall's figures give one the 

 impression that L. riciniformis is a proportionately less elongated shell 

 and with more convex sides than L. elongata. 



Lingula obtusa, Hall. 



Lingula obtusa, Hall 1847. Pal. N. York, vol. I., p. 98, pi. 30, 



figs. 7, a-c. 

 Billings 1863. Geol. Canada, p. 161, fig. 137. 



Cat Head, Lake Winnipeg, T. 0. Weston, 1884 : one nearly perfect 

 and beautifully preserved specimen and two very bad ones. The only 

 one that is well preserved is nearly flat, a little broader in advance of the 

 midlength than behind it, and therefore slightly more ovate than oval in 

 outline. Its surface markings consist of crowded and prominent, minute 



* Lower Silurian Braohiopoda of Minnesota, p. 314. 



