22 THE FIRST DIVERS 



are plainly visible. The posterior end is very wrinkled, and 

 after a few minutes these wrinkles begin to smooth out 

 and a conical projection appears. This increases in length 

 and slenderness and a very thin tube emerges from the tip. 

 Like a telescope the jointed tail draws out and out until it 

 is almost ten times as long as the maggot. When at last it 

 has reached the surface, the tip opens and air is drawn 

 down into the respiratory system of the animal, and from 

 now on it crawls about, burrows and feeds, and although 

 perhaps five inches below the surface, yet it draws a con- 

 stant stream of air down into the body. 



So when I have descended the diving ladder in a helmet 

 and clamber about several fathoms down with the air 

 coming to me through the hollow rubber hose, I am only 

 a poor imitation of a rat-tailed maggot, which keeps its 

 very efficient air tube telescoped within its own body, 

 sending it out and up whenever necessary (Fig. 3) . 



Spiders are the most amazing of creatures living on the 

 earth, and if in long past ages they had had the added 

 advantage of size they might today be dominant, while 

 we still crept fearfully about in the trees. Their multi- 

 plicity of keen eyes, their octet of strong limbs with cun- 

 ning, hand-like claws, their marvelous supply of thread 

 and cable, ribbon and net fashioned from the warp and 

 woof of their own body, and especially the subtle instincts 

 which dictate their habits — all these have enabled spiders 

 to reach out and become successful in many strange ways 

 and unexpected places. 



