The thoracic limbs, in front of the genital segments, are not as a rule differentiated into anterior maxillipedes and posterior locomotive appendages, as in higher forms; we have seen, however, that all these limbs take part in the prehension of food, and except in the Limnadiidae they all assist in locomotion. One of the middle thoracic legs of _Artemia_ (Fig. 8, A) has a flattened stem, with seven processes on its inner, and two on its outer margin. The gnathobase (_gn_) is large, and fringed with long plumose setae, each of which is jointed; this is followed by four smaller “endites” (or processes on the median side), and then by two larger ones, the terminal endite (the sixth, excluding the gnathobase) being very mobile and attached to the main stem by a definite joint. On the outer side are two processes; a proximal “bract,” a flat plate with crenate edges, partly divided by a constriction into two, and a distal process, cylindrical and vascular, called by Sars and others the “epipodite.” In other Branchipodidae we have essentially the same condition, except that the fifth endite often becomes much larger than in _Artemia_, throwing the terminal endite well over to the outer edge of the limb; such a shift as this, continued farther, might well lead to the condition found in the Limnadiidae, or Apodidae, where the lobe which seems to represent the terminal endite of _Artemia_ is entirely on the outer border of the limb, forming what most writers have called the exopodite (Lankester’s “flabellum”).[18] In the two last-named families the basal exite or bract of the Branchipodidae does not appear to be represented. [Illustration: FIG. 8.—=A=, Thoracic limb of _Chirocephalus diaphanus_; =B=, prehensile thoracic limb of male _Estheria_. _gn_, Gnathobase; 1–6, the more distal endites. ] The limbs of the Apodidae are remarkable in two ways; those in front of the genital opening (very constantly ten pairs) are not so nearly alike as in most genera of the sub-order, the first two pairs especially having the axis definitely jointed, while the endites are elongated and antenniform; further, while the first eleven segments bear each a single pair of limbs, as is usual among Crustacea, many of the post-genital segments bear several pairs; thus in _Apus cancriformis_ there are thirty-two post-cephalic segments in front of the telson, the first eleven having each one pair of limbs, while the next seventeen have fifty-two pairs between them, the last four segments having none.