OUR CAHCINOLOGICAL FRIENDS. 



99 



THE HORSESHOE CRAB: IS IT A GIANT SPIDER-FORM? 



Those among us to whom the horseshoe crab, or 

 king-crab as it is frequently called, in allusion to 

 its large size, is known 

 only in its general de- 

 tails, would probably 

 scarcely think it worth 

 while to consider the 

 question as to its posi- 

 tion in the animal 

 world. What should 

 it be other than the 

 ' crab' that it has al- 

 ways been considered ? 

 With our carcinologi- 

 cal friends it agrees 

 in the possession of a 

 crusty envelope or 

 shield, it breathes by 

 means of gills, inhabits 

 the water or mud like 

 them, and has, more- 

 over, the end-joints of 

 the legs pincered (che- 

 late). Further, it peri- 

 odically sheds its shield like the crabs. But relent- 

 less and pursuing science has shown that in many 

 points of structure the animal is closely related to 

 the scorpions, and perhaps even more closely than 

 to the entire group of crust-bearing animals as such 

 (crabs, shrimps, lobsters, etc.). This relation is seen 



Horseshoe cbab. 



