464 



INVERTEBRATE MORPHOLOGY. 



lum, being only about a millimetre iu breadth, while the 

 purple Pkoxichilidium measures over three millimetres from 

 tip to tip of the legs, and the deep-sea form Collossendeis has 

 a span of over sixty centimetres. The body proper is compar- 

 atively small, the four pairs of long legs which arise from the 

 thorax being exceedingly conspicuous, a feature which has 



FIG. 213. Phoxichilidiiim maxillare (after MORGAN). 



suggested the term Pantopoda sometimes applied to the 

 group. Anteriorly there is a well-marked proboscis carrying 

 the mouth at its anterior end, and at the base of this there 

 arise the cheliceme, which are rather short chelate limbs. 

 The next segment of the body succeeding that which bears 

 the chelicerae bears upon its dorsal surface the eyes, and may 

 be regarded as a fusion of three segments since it bears three 

 pairs of appendages. The most anterior of these are slender 



