i88 
BULLETIN OF THE BUREAU OF FISHERIES. 
ently. The two small chelate legs are also drawn up rapidly to the mouth, as if to 
hand up pieces of food. 
When stimulated in this way, the plates of the first pair of maxillae come together 
over the lower posterior half of the mandibles. The movements of the masticatory 
parts of the second maxillae are synchronous with the beating of the scaphognathite. 
These leaf-like plates project somewhat obliquely over the convex surfaces of the jaws, 
and are directed inward and slightly upward. The large plates of the first maxillipeds 
work up and down and at the same time inward toward the middle line, describing an 
ellipse. The second pair of maxillipeds move alternately or together, inward and out- 
ward, with slight up-and-down movement. The large maxillipeds move together, the 
toothed margins meeting like the jaws of a nutcracker, while the three terminal joints 
are bent inward and somewhat downward, as in the case of the second maxillipeds, 
so as to meet on the middle line below and hold the food up to the mouth. (For full 
analysis of the mouth parts, see ch. vi, p. 227.) 
CANNIBALISM. 
Lobsters are cannibals from birth, owing, primarily, to their strong instinct of 
pugnacity. The small, as well as the large, are ever ready to prey upon those still 
smaller or weaker than themselves. This is certainly true of all the lobsters which have 
been kept under observation in the restricted space of hatching jars or aquaria and 
where suitable food in suspension was either lacking or insufficient. In their natural 
environment in the sea, however, where the young are quickly and widely dispersed, 
opportunities for the display of this tendency could seldom arise. In the early stages, 
at least, it is questionable whether cannibalism would occur under any conditions, 
provided the larvse were properly fed. 
When crowded in cars or pounds, lobsters play the role of cannibals at a great rate. 
As Mr. F. W. Collins remarked to me in 1902, persons not understanding this will lose 
20 per cent of their stock in a very few days. He usually counted on a loss in crowded 
cars of 5 per cent in the course of three days, the larger feasting on the smaller, even 
when the precautions of supplying them with food and separating the “soft shells” 
had been duly taken. 
REVIEW OF THE INSTINCTS AND INTELLIGENCE OF THE ADULT LOBSTER. 
The instincts of fear and of concealment by burrowing or hiding in seaweed or 
under stones; the restless activity of the lobster in exploring the bottom for food, feel- 
ing its course by whipping the water with its long antennae, and testing all objects 
with both these and its sensitive feet, or smelling its way to food by beating its anten- 
nules, even seeming at times to stalk and approach its prey by stealth; storing up food 
or, at least, dragging dead prey into its burrows or sometimes burying it, to be after- 
wards exhumed, thus recalling a well-known trait of the dog; the fighting instinct so 
often displayed between members of its own race and not confined to captives, which 
brings into play all its caution and characteristic attitudes in attack and defense; its 
