2 INTRODUCTION. 
machine which propels it, and the latter is placed in a subordinate 
relation. — 
In one group, that of nets, convenience in arrangement of the speci- 
mens seems to demand that material, a character of small importance, 
shall be made prominent. Two widely diverging groups of apparatus 
are associated under the head of nets, viz, encircling-nets, the true rela- 
tions of which are with grasping and scooping instruments, and entang- 
ling nets which belong with the traps, where a third group of nets, the 
pound and weir nets are actually classed. Where the exigencies of 
administration of the specimens demand that they should be arranged 
otherwise than in their exact systematic position, full cross-references 
are given. 
The simplest implements have always been placed first, the series 
advancing in the order of complication of structure. Thus we have 
in the beginning the apparatus of direct application, or tools, including, 
first, those inplements which are used in the band, and which increase 
its power in a simple way, such as clubs and slung-shot, which merely add 
to the weight of the fist, followed by the knives, axes, and spears, which 
in their simplest and primitive form were sharpened stones and pointed 
sticks. Second, are the grasping-implements, or those by which the 
power of the fingers is extended. In this series the same principle of 
progress from simple to complex is followed; in the scoop we have the 
idea of the hollow palm of the hand developed in various forms, while the 
‘grasping-hooks and grasping-lines are the artificial extensions of the 
human finger. Under hooked instruments, the simple hooks, or those 
which are attached to the object by a single motion, a pulling one, are 
placed first, followed by the barbed implements, in which the attach- 
ment is made by a thrusting, succeeded by a pulling motion, and then 
by the tongs and forceps, which are essentially double hooks. The suc- 
ceeding division is that containing the lasso and bolas, which are 
worked at long distances and require great skill, succeeded by the 
tangles, which are, in principle, assemblages of lassos, entangling objects 
among their fiber nooses. 
In the third division, that of missiles, the same principle of succession 
isadhered to. First are placed those missiles which are propelled by the! 
unaided arm; then those in using which the arm is artificially length-! 
ened, as with the sling, string, or darting stick; then those in which the, 
propelling power is derived from the elasticity of rods and cords, the 
strength of the arm having become subsidiary; closing with those in. 
