Evans, "On Onychophora from the Siamese Malay States," Quart.
Peripatus, though indubitably an Arthropod, differs in such important respects from all the old-established Arthropod classes, that a special class, equivalent in rank to the others, and called Prototracheata or Onychophora, has had, as we have seen, to be created for its sole occupancy.
Very usually (but not in the Onychophora = Peripatus) all the parapodia are plated with chitin secreted by the epidermis, and divided into a series of joints - giving the " arthropodous " or hinged character.
Of these facts is given by saying FP, Rudimentary frontal pro that the Onychophora are " deutercesses perhaps repre ognathous " - that is to say, that senting the prostomial the buccal somite carrying the mantentacles of Polychaeta.
It may be pointed out that the most radical difference presented in this list is that between appendages consisting of the corm alone without rami (Onychophora) and those with more or less developed rami (the rest of the Arthropoda).