Expedition to British America. 167 



Length 23 mm., width 36 mm., height of hinge area 16 

 mm., width of foramen at base 10 mm. 



This fine species, which is named in honor of Professor T. 

 H. ISIcBride, of the State University of Iowa, is found some- 

 what sparingly distributed in the Rockford shales of Devonian 

 Age, at Rockford and Hackberry Grove, Iowa. 



ME OX EXPEDITION TO BRITISH AMERICA. 



Bv C. C. XUTTIXa. 



During the summer of 1S91, Mr. A. G. Smith and Frank 

 Russell, and Prof. C. C. Nutting, of the State University of 

 Iowa, were engaged in zoological explorations on the shore 

 of Lake Winnipeg and on the lovv-er Saskatchewan river. 

 The results of this expedition have not yet been worked up 

 for publication, but this opportunity is taken to acknowledge 

 the valuable aid and facilities rendered the party by the B., C. 

 R. & N. R. R., the various Canadian officials with whom the 

 expedition came in contact, Capt. Wm. Robinson, of West 

 Selkirk, Manitoba; the officers in charge of the Winnipeg 

 Station of the A. Booth Packing Co., of Chicago, and the 

 various agents of the Hudson Bay Company in the regions 

 visited. 



