THE HORSESHOE CRAB 



group of animals that flourished in the Devo- 

 nian period, and, while neither fish nor crab, 

 they combined certain features of both. To 

 these relations of our humble horseshoe crab 

 is given, therefore, somewhat tentatively it 

 may be, the distinguished honor of being the 

 progenitors of the vertebrates, of linking this 

 highest group of animals with the lowly inver- 

 tebrates, of bridging the yawning chasm be- 

 tween the back-boned and the back-boneless. 



When one meets a horseshoe crab, there- 

 fore, it is well to treat him with respect for 

 the sake of the trilobite and the ostracoderm 

 with their strange histories. His days are 

 probably numbered, for, although he is abun- 

 dant in these regions, there are only two liv- 

 ing species left in his class, one, this friend 

 of ours of the marsh and beaches, which ex- 

 tends its range from Maine to Mexico, the 

 other, a species that lives on the eastern Asi- 

 atic coast. 



In the early part of the summer these 

 strange beasts are busy depositing their eggs 

 in all the sandy and muddy estuaries. They 

 go about in pairs, the larger female, often 

 dark and weather beaten, followed tena- 

 ciously by the smaller male. Later in the 



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