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Show 238 DR. ST. GEORGE MIYART ON THE [Feb. 4, the cup-like depression above noticed. Each lateral half of the parahyal arch has, medianly, a gentle outward curve. The urohyal is decidedly longer than in the Lories, and consists of two parts-(1) a longer, proximal portion (u), which somewhat expands to its termination, where it is truncated; and (2) a very much smaller distal portion (ud), about half the length of the proximal part. It may well be that a distinct distal part of the urohyal also existed in the species before described, but had become detached, since as to several of them it was remarked that the urohyal was truncated at the hinder end. The entoglossum (e) differs greatly from that of the LORIID^; before described in that it is relatively, as well as absolutely, much longer and more slender. Each lateral half, each entoglossal, has the part in front of the isthmus, which joins it to its fellow, more than twice the length of the part behind the isthmus. The anterior parts of the two entoglossals are slender, curve outward from each other towards their preaxial ends, and terminate almost in a point. Just in front of the median bony isthmus the ventral border of the entoglossal sends downward and outward a marked process (al), the anterior lateral process; behind this is a sharp but very narrow concavity, bounded postaxiahy by a process (pi) which extends slightly downward and much inward to join its fellow of the opposite side, and so forms the concavo-convex articular surface for junction with the concavo-convex articular surface of the front end of the basihyal. The part of each entoglossal behind the isthmus curves a little upward and inward, and then downward and outward, terminating in a slightly rounded extremity. At the summit of the curve there is a slight prominence (all) on the dorsal margin, which may be called the dorsal lateral process. The hypobranchicds are about as elongated as in Lorius \ but nearly straight. The ceratobranchials are about half length of the hypobranchials, and are slightly curved concave mesiad. Thus the genus Nestor shows a very interesting, but hardly surprising, affinity to the LORIID^E as regards the structure of the hyoid. It has a parahyal arch, but that arch is remarkable for its slenderness, as the entoglossals are distinguished by their length and slenderness, and differ decidedly in form from those of Eos, Lorius, and Trichoglossus. Thus considered, the Nestors may be thought to represent the Lories in the N e w Zealand region. The interest I felt, however, in examining the hyoid of Nestor was greatly exceeded when I turned to the examination of that of Nanodes, formerly known as Lathamus. The true position of this species and its relationship or non-relationship to the Lories have been matters of controversy, 1 P. Z. S. 1885, p. 168, fig. 3. |