1893.] Zoology. 741 
ZOOLOGY. 
Zoology of the Lower Saskatchewan River.— Prof. C. C. 
Nutting's report on Zoological Explorations on the Lower Saskatche- 
wan River is condensed statement of a large amount of information. 
The expedition was sent out by the Iowa State University, with the 
primary object of getting a series of birds in summer plumage, and 
also the downy young. Prof. Nutting, however, got all he could in all 
directions. Much of the interest of the report lies in the descriptions 
of the habits of the various animals, either as observed by the party 
themselves, or told them by the hunters of that region. 
In speaking of the geography of the country explored, Mr. Nutting 
refers to the water system as comparable in extent to that of the Mis- 
sissippi River. From the Saskatchewan River to the Polar Sea is one 
inextricable maze of lakes, rivers and marshes, one of the greatest 
palustral regions in the world, perhaps, and the breeding place of 
most of our migratory birds. 
The rezion is one of unusual zoological interest, being to a certain 
extent characterized by an intermingling of eastern and western, arc- 
tic and temperate fauns. The whole region is covered with dense 
forests of conifers and poplar. The formation is Upper Silurian, and 
the principal paleontological feature is Pentamerus decussatus of which 
a fine series was secured. 
The birds collected, numbering 104 species, were the summer resi- 
dents of that region, of which 90 per cent are birds included in the 
avifauna of Iowa. 
In regard to the migration of birds, the view held by the writer is 
that the impulse to migrate comes from without and the act is a con- 
scious seeking for a more suitable clime, on the part of the adults at 
least, the young simply following or imitating their elders. There is 
much to indicate that this stimulus comes in the form of the wind. 
Only a fragmentary list of the mammals is given. One snake was 
found, also three frogs and five fishes ; but a large number of insects 
and molluses were secured. (Bull. Lab. Nat. Hist. Iowa State Uni- 
versity Vol. II, No. 3, 1893). 
Zoological News. General.—A correspondent of The Nat- 
uralist has communicated a curious fact to that Journal. Along the 
estuary ofthe Humber Riveran excavation has been made in a quarry 
