Description of Genera and Species. 35 



organs to be studied. The endopodites are all much laterally compressed and set along 

 their edges with more or less regularly placed bristles and with tufts arranged in lines 

 alons their sides. As in Tealliocaris, the first of these legs is more massive than the 

 succeeding ones. The leys become longer and larger in succession, the penultimate 

 joint being the longest and the terminal joint spatulate and with no terminal claw. 

 The backward flexing of the limb occurs at the articulation between the second and 

 third joints from the tip. The actual basal joints have not been observed ia this specimen. 

 Fragments of the exopodites of five of these limbs are seen, and also that of the seventh 

 limb. One of these, probably the fifth, shows the usual muscular basal joint and part 

 ot the manj' -jointed swimming lash, which is particularly strong. The others are 

 represented by portions of the lash. These cannot be far out of place relatively to their 

 respective endopodites, for the gills are found interposed between these two structures. 

 A seventh leg is probably hidden under the portion of the carapace which has not been 

 removed, for a lash and a gill are seen placed relatively to one another outside the fragment 

 of carapace as if this were the case. The gills appear to be lobulated as in TeaUiocaris. 

 An exopodite, probably belonging to the right side, is seen projecting from the right 

 postero-lateral angle of the carapace. Fragments of the seven endopodites and their 

 corresponding exopodites are shown on the left side of the body in fig. 2 with a pellicle 

 of shale separating them from the carapace. Six flattened quadrate-shaped plates 

 intervene between these undoubted limbs and tlie wide sternal plates. The anterior 

 margin of each plate overlaps on to the plate in front in turn, and the plates are arranged 

 so as to appear to be placed opposite the interstices between the margins of the sternites. 

 The plates, moreover, seem to l)e hollow or made up of two layers of the test, which is 

 delicate and thin and much pitted. These are, in all probabilit}-, identical structures to 

 those which Huxley in his figures of Pygocephalus cooperi^ (figs. 8, 9) has interpreted 

 as the coxal or Ijasal joints of the limbs, but the mode of their occurrence in the present 

 species is more suggestive of their being of the nature of epipodites like the plates found 

 in the recent Anaspides described by Caiman" (pl. viii., fig. 11). Although not described, 

 there are small structures similarly placed in TeaUiocaris.^ Small epipodites furnished 

 with sensory hairs are also found on the basal joints of the limbs in Gnathophausia.* 

 Caiman tlnnks that the plates in Anaspides function as gills, as they easily could in such 



' Loc. cit., pl. xiii., figs. 1, 2, ."5. 



- Caiman, Tians. Roy. 8oc., Eiliii., 1897, vol. .x.xxviii., p. 787., pl. xxxviii., fig. 1. 

 'Pl. i., tig. 7a. 



HI. O. Sar.s, "Report on tlu' Scliizopoda." Results of Voyage of H.M.S. Cliallenger 1873-1S76., pl. 

 viii., tigs. 9, 10. 



