NATURAL HISTORY OF THE AMERICAN LOBSTER. 
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By FRANCIS HOBART HERRICK, Ph. D., Sc. D., 
Professor of Biology, Western Reserve University, Cleveland, Ohio. 
Chapter I.— THE LOBSTERS AND ALLIED CRUSTACEA; THEIR ZOOLOGICAL 
RELATIONS, HABITS, DEVELOPMENT, AND USE AS FOOD. 
NATURAL HISTORY OF THE CRUSTACEA. 
Nature works according to definite principles, and with a degree of uniformity which 
for most of our purposes is practically absolute. Accordingly we find that whenever 
an animal or plant has been successfully domesticated or whenever the young of any 
form have been successfully reared by the artificial impregnation and subsequent care 
of the eggs, as in the case of the oyster or the whitefish, this has been accomplished by 
acting, whether intelligently or not, in accordance with the principles of nature. The 
mollusk or the vertebrate is made to yield to experiments which a knowledge of its 
habits and structure would suggest. In the lobster we have to deal with another and 
distinct type, for although this animal swims in the sea, it is not a fish, but an arthropod, 
and a knowledge of the ways of fishes and mollusks will help but little in the study of 
its habits or in the propagation of its race. 
The following paragraphs on the general characteristics of the arthropods will be 
of little dr no use to professional zoologists, but may help to set our subject in a clearer 
light for other readers. 
Of the eight or more animal types recognized by naturalists the arthropods are 
distinguished for their complicated structure and wonderful diversity of form, for the 
wide range and specialization of their instincts, their almost unparalleled fertility and 
corresponding activity. In the latter respect, at least, some of the insects are not sur- 
passed by birds, the most active vertebrates. 
The body of the arthropod is composed of a series of successive segments, the 
somites or metameres, which in conformity to vertebrate anatomy are divided into three 
groups, pertaining to the head, thorax, and abdomen. (PI. xxxm, and table 4.) Theo- 
retically, each somite at one time possessed a pair of jointed limbs, and many of the seg- 
ments still retain them. In the living adult state, the body is normally maintained in a 
definite upright position, which is often one of unstable equilibrium, whether the animal 
is in motion or at rest. These characteristics are shared in some degree by the annelid 
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