BODY AND LIMBS 



SOS 



or " chelophores," the second or " palps," the third, the false or 

 " ovigerous " legs, and the first of the four pairs of " ambulatory " 

 legs. The chelophores bear their chela, or "hand," on a stalk 

 or scape ; the ambulatory legs are constituted of three coxal joints, 

 a femur, two tibial joints, a tarsus, and a propodus, with its claws, 

 and with or without auxiliary claws. 



The Body. — The trunk with its lateral processes may be still 

 more compact than in Pycnogonum, still more attenuated than 

 in Nymplion. 



In a few forms (e.g. Pallene, Ammothea, Tanystylum, Colos- 

 sendeis) the last two, or even more, segments of the trunk are 



A B C 



Fig. 265. — A, Colossendeis prohoscidea, Sabine, Britain ; B, Ammothea echinata, Hodge, 

 Britain ; C, Plioxichilus spinosus, Mont., Arctic Ocean. (The leg.s omitted.) 



more or less coalescent. In Rliyncliothorax the cephalic segment 

 is produced into a sharp-pointed rostrum that juts forward over 

 the base of the proboscis. The whole body and limbs may be 

 smooth, tuberculated, furnished with scattered hairs, or some- 

 times densely hispid. 



The proboscis varies much in shape and size. It may be 

 much longer or much shorter than tne body, cylindrical or 

 tumid, blunt or pointed, straight or (e.g. Decolopoda) decurved ; 

 usually firmly affixed to the head and pointing straight forwards ; 

 sometimes {Eurycide, Ascorhynchus) articulated on a mobile stalk 

 and borne deflexed beneath the body. 



Chelophores. — The first pair of appendages or chelophores 

 are wanting in the ' adult Pycnogonum, PJioxicJiilus, PJiynclio- 

 thorax, and Colossendeis} 



' Hoek, Ohall. Rep. p. 15, mentions a specimen of Colossendeis gracilis, Hoek, 



