Aquarium Number 



PREPARED BY THE ASSISTANT DIRECTOR OF THE AQUARIUM. 



ZOOLOGICAL 

 SOCIETY BULLETIN 



X umber Jfi 



Published by the New York Zoological Society November, 1911 



THE SPIDER CRAB. 



OF all the weird creatures that make their 

 home at the bottom of the sea, perhaps 

 none is more extraordinary than the spider 

 crab. The spine-covered body, the extremely 

 long appendages, the movements, slow to the 

 limit of deliberation, and, above all, the habit 

 of decorating its body and sometimes its limbs 

 as well with all sorts of odds and ends of mate- 

 rial for the purpose of concealment, render it 

 as interesting an object for study as could well 

 be found. 



They range in size from tiny forms to the 

 giant Japanese deep sea crab with a spread of 

 legs reaching as much as twelve feet — by far the 

 largest of the crustaceans. Spider crabs occur 



all over the world in both cold and warm seas 

 and from the shore line to great depths. Natu- 

 rally, with such a wide distribution there are 

 many genera and species, and several of these 

 are found in our own region. 



The commonest species of our coast are the 

 well known large brown ones, constituting the 

 two species of the genus Libinia (L. emarginata 

 and L. dubia), probably not distinguished as 

 separate by the ordinary observer though there 

 is a difference in the number of spines on the 

 carapace. These crabs are unable to swim except 

 in the larval stage, and in walking they raise 

 themselves upon their awkward-looking legs 

 after the manner of gigantic daddy long-legs and 



6«»0 <*iz 



