Insectivora. ^MAMMALIA. Insectivora. 
XXIX 
Order IV.— INSECTIVORA.'*' 
The Insect-eaters are characterized by having varia- 
ble canine and incisor teeth, the molars being prism- 
shaped, with acute cusps. 'J’he feet are plantigrade, 
and provided with claws ; the digits are not elonga- 
ted, nor thumbs opposable. The clavicles are com- 
plete. As an Order, these creatures are not largely 
represented in America. They are not found at all 
in South America, nor in Australia. It is an interest- 
ing fact that those regions that form the exceptions, 
are inhabited by Marsupials ; the latter being, as is well 
known, found in no other. One genus — Solenodon — 
which has given much trouble, in so far as its true 
place is concerned, is found in Cuba and St. Domingo. 
Some, as the North American Shrews, are found as 
far south as Mexico. 
'J'he food of these animals, as the name imports, is 
almost exclusively insects, worms, snails, etc. The 
teeth are found to be admirably adapted to their work, 
being provided with cutting edges for tearing, and 
flat surfaces for grinding their food. 
Many of them live under ground, subsisting on 
worms obtained in the long and winding furrows, 
which they construct in connection with their nests. 
As mild and harmless as they seem — and no animal 
looks more so than a Mole or Shrew— they are really 
most vicious. They fight with exceeding fury, and 
the victorious curiously emulates the example of the 
lord of the forest, by scalping and mutilating his 
enemy. They are also excellent swimmers, being able 
to cross quite sizable streams. 
Extinct Insectivora. 
The first traces of Mammals found by geologists 
were Insectivorous Marsupials. Remains, also, have 
been found at a very early date, which are referred 
by some to the true Insectivores. The Stereogna- 
thus, from Stonesfield beds, is claimed to be of this 
Order, though by others to be of the Ruminantia. A 
lower jaw of a small so-called insectivorous animal, 
named Spalacotherium, was found in the Purbeck 
beds; thus placing Mammalia midway between the 
older Oolitic and the older 'I'ertiary Periods. The in- 
sect nature of these ancient forms is indicated by the 
presence of insects in large numbers in the Purbeck 
beds. In the Tertiary beds numerous remains are 
found, which have received the following generic 
names : Dimylus,Geotrypus, Ilyporysius, Palreospalax. 
Talpa europea has been found fossil in the bone caves 
of Europe, T. coeca in Italy, 'I.', minuta in South 
France, Dimylus paradoxus in Miocene beds at 
Weissenau, Oeotrypus acutidens in Miocene of Au- 
vergne, G. antiqus. in freshwater Miocene, Auvergne, 
Hyporysius tellurus. South France ; Galeospalax myg- 
daloides in Auvergne, Palmospalax magnus in Ostend. 
Sorex foidens has been found fossil in England. 
S. araneus from France. Seven species of Sorex have 
been taken from the Miocene of France. A genus — 
Mysarachne — with one species from Auvergne, and 
Plesiosorex talpoides, from the same. In Sansans, 
France, a Blarina. 
A well-approved arrangement of the members of 
this Order is that of Dr. J. A. Wagner, in tlie fifth 
volume of his supplement to Schreber's Saugthiere, 
published in 1855. Five families are established, as 
follows : Dermo'ptera, Indian Archipelago ; Scanden- 
tia, India, Borneo and Java ; Soricidce, East Indies, 
Europe, Africa, North America; Talpidm, spread 
over the whole world, save South America and New 
Holland ; Aculeata, confined to the Old World. Of 
these, only two families concern us, viz : SoricidiB 
aud Talpidm. 
Family— SORICID^. 
The ancient naturalist, Pliny, has left us the term 
Sorex, a Shrew-mouse, which is now embodied in the 
present family designation. The Shrews are Mouse- 
like in appearance, with a considerably elongated 
muzzle. There are no distinguishable canines, excejit, 
perhaps, in some cases spurious ones. The bony 
annulus of the orbit is wanting, or imperfect. The 
ear has a distinct concha. The feet are regular and 
normal, the anterior pair being smaller than the pos- 
terior. 'I'hese characters of feet and ears distinguish 
it readily from the Family Talpidm. On the sides of 
the tail of these creatures are peculiar glands. 
Sub-Family— SORICINAil. 
Under this head we have three genera, belonging 
to North America, viz : Neosorex, Sorex and Blarina. 
These are spread over the whole of the northern 
hemisphere, some being seen very far in the North. 
The region of the Rio Grande is their southernmost 
limit, though, in the Old World, species are found in 
Southern and Central Africa. 
The genus Sorex includes the larger number of the 
American species. The largest forms are found in 
the genus Blarina; and these are quite unlike any 
of the Old World. 
Neosorex. 
This genus, established by our accomplished Amer- 
ican naturalist. Prof. S. F. Baird, is characterized by 
having the ears rather short, and partly furred on 
both surfaces ; they are also valvular in form. The 
dental formula is given as follows: Anterior Incisors, 
I ; Lateral Incisors and Premolars, f-f ; Molars, ; 
= 32. The upper anterior incisor has a well-defined 
hook at the base, the lower one with two tubercles 
and a notch. 'I’he first two upper premolar teeth 
are equal, and larger than the fourth, which exceeds 
* For much of the material under the present and succeeding Orders, we have drawn upon the U. S. Pacific R. R. Rejp</rts of 
Explorations and Surveys. Zoology by Prof. S. F. Baird. 
