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Handbook of Nature-Study 



A crayjish. 

 Drawn by Anna C. Stryke. 



The mother crayfish has another use for her swimmerets ; in the spring, 

 when she is ready to lay eggs, she cleans off her paddles with her hind legs, 

 covers them with waterproof glue, and then plasters her eggs on them in 

 grapelike clusters of little dark globules. "What a nice way to look after 

 her family! The little ones hatch, but remain clinging to the maternal 

 swimmerets, until they are large enough to scuttle around on the brook 

 bottom and look out for themselves. 



The breathing apparatus of the crayfish cannot be seen without dissec- 

 tion. All the walking legs, except the last pair, have gills attached to 

 that portion of them which joins the body, and which lies hidden under- 

 neath the sides of the carapace or shell. The blood is forced into these 

 gills, sends off its impurities through their thin walls and takes in the 

 oxygen from the water, currents of which are kept steadily flowing for- 

 ward. 



Crayfishes haunt still pools along brooksides and river margins and 

 the shallow ponds of our fresh waters. There they hide beneath sticks 

 and stones, or in caves of their own making, the doors of which they guard 

 with the big and threatening nippers, which stand ready to grapple with 

 anybody that comes to inquire if the folks are at home. The upper sur- 

 face of the crayfish's body is always so nearly the color of the brook bot- 

 tom, that the eye seldom detects the creature until it moves; and if some 

 enemy surprises one, it swims off with terrific jerks which roil all the 

 water around and thus covers its retreat. In the winter, our brook forms 

 hibernate in the muddy bottoms of their summer haunts. There are 

 rnany species; some in our Southern vStates, when the dry season comes on, 

 live in little wells which they dig deep enough to reach water. They heap 



