ORDER TRACHEARLE. 
499 
or like a trefoil. It carries at its base the forceps and the 
palpi. The forceps are cylindrical or linear, simply prehensile, 
composed of two pieces, the last of which is pincer-like, with 
the lower claw, or that which is immoveable, sometimes 
shorter. The palpi are in the form of a thread, of five, or 
nine articulations, with a hook at the end. Each following 
segment, with the exception of the last, serves as an attach- 
ment to a pair of feet ; but the first, or that with which the 
mouth is articulated, has on the back a tubercle, carrying on 
each side two simple eyes, and underneath, in the females 
only, two other small feet, folded back upon themselves, 
and carrying the eggs which are assembled all around them, in 
one or two pellets. The last segment is small, cylindrical, 
and pierced with a little hole at its extremity. No vestiges 
of stigmata are discoverable. 
These animals are found among marine plants, sometimes 
under stones, near banks or shores, and sometimes also on 
cetaceous animals. 
Pycnogonum, Brim., Mull., Fab., 
Are without forceps or palpi, and the length of their feet but 
little exceeds that of the body, which is proportionably shorter 
and thicker than in the following genera. They live on the 
cetacea. 
Phoxichilus, Lair., 
Present no palpi, as in the preceding, but have very long feet, 
and two antennae-pincers. 
Nympiion, Fab., 
Resemble the Phoxichili, in the very narrow and oblong form 
of their body, the length of their feet, and the presence of 
antennae-pincers, or forceps ; but they have, besides, two 
palpi. 
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