OCR Text |
Show 358 PROF. A. H. GARROD ON THE [Apr. 1, also pointed anterior ends, running inwards almost as much as does the second, in a manner very characteristic of all the genera in which the second semiring is pointed and prolonged. There is no trace ot any interval between the penultimate and last tracheal rings. Between the last and the first bronchial semiring the interval is a capacious ovoid. That between the first and second bronchial semirings is elongate and shallow, not deeper than the lower bronchial intervals. Caccabis saxatilis agrees with C. rufa, except that in the former there is a slight development of antero-lateral interannular intervals between the lower tracheal rings, as in Argus, the account of which follows. In Argus giganteus tbe lowermost tracheal rings are separated by Fig. 5. Fig. 6. Front view. Back view. Argus giganteus. narrow intervals in front, where in the middle line the last three fuse and ossify into a mass whose lower border descends but little below the level of the inferior margin of the unmodified last ring for the articulation of the anterior extremities of the first bronchial semirings. Posteriorly the pessulus joins the penultimate ring, the two hinder ends of the last ring being well separated. The first bronchial semiring is large and strongly convex downwards from the development at each of its ends of upturned articulating processes, at the junction of which with the horizontal portion of the tube the second semiring articulates along its lower border. The interval between each lateral element of the last tracheal ring and its corresponding first bronchial semiring is considerable, tending to a quadrate form, whilst that between the first and second semi- |