250 



THE RISE OF 



Fig. 11-50. Centipedes have numerous jointed legs. 

 Some tropical forms are nearly a foot long and can 

 inflict a painful wound in a man. This is a smaller 

 form common in the U. S. 



ANIMAL LIFE 



into her genital pore. Sometimes the female 

 proceeds to devour her unsuspecting mate, 

 but such is not always the case, and he may 

 succeed in escaping. She then spins a tiny 

 ball in which the eggs are laid and often 

 carries it around with her. It is with con- 

 siderable difficulty that this ball of eggs can 

 be removed from the female spider. She 

 takes it with her everywhere and guards 

 it very closely. But after the young have 

 hatched, they are on their own. 



The scorpion (Fig. 11-48) is an elongated 

 relative of the spider, with large, fierce- 

 looking pincers held out in front. The long 

 abdomen also terminates in a sharp-pointed 

 sting which inflicts an irritating wound on 

 man and a fatal one for the insects and spi- 

 ders which make up its primary diet. It is 

 active at night and hides by day under 

 logs and rocks. The "matins; dance " of the 

 scorpions has been described in detail by 

 many observers and is a very interesting 

 event. 



The horseshoe or king crab (Fig. 11-49) 

 another arthropod, is of interest because it 

 belongs to a very ancient group and is 

 therefore sometimes referred to as a livins; 

 fossil. It inhabits our Atlantic coastal waters 

 from Maine to Central America and its molt 

 is a common sight, if not the animal itself. 

 For some strange reason, this surviving spe- 

 cies of the arthropods which lived long ago 

 (Cambrian period) has been able to con- 

 tinue down to tlie present, while its millions 

 of relatives have become extinct. 



The many-legged centipedes (Fig. 11- 

 50) are commonly found under stones and 

 logs where they remain inactive during the 

 day. At night, however, they move swiftly 

 about in search of their favorite food, earth- 

 worms and insects. They possess a pair of 

 poison claws on the first segment which are 

 effective instruments in securing prey. Some 

 of tlie tropical centipedes reach a length of 

 10 inches, and their bite, while not danger- 

 ous to man, is certainly painful. In temper- 

 ate zones the most common is the house 



