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Show 1893.] THE ANATOMY OF PARROTS. 513 Gadow1 describes the peroneus longus as apparently absent in Chrysotis. In the other genera examined the muscle is intermediate between Stringops and Ghrgsotis; it rises from about the middle third of the leg as high as the tip of the bony fibula, and only slightly overlaps the peroneus brevis. The insertion of the peroneus longus is always into a strong fibro-cartilaginous ring which surrounds the deep flexor tendons opposite the ankle-joint and is attached to the base of the tarso-metatarsus. The peroneus brevis varies very little; it rises from the outer surface of the tibio-tarsus and is inserted into the outer part of the posterior surface of the base of the tarso-metatarsus. In Chrysotis, where the peroneus longus is so small, it is larger than usual. We do not propose to produce as a result of the above notes a complete scheme of classification of the Psittaci : in the first place we have been unable to see a good many types which ought to be studied before a general scheme should be propounded ; aud in the second place w e have only called attention to certain points in the anatomy of the group. It may, however, be pointed out that the material which we have gathered together in this paper, combined with what we know through the researches of the late Professor Garrod, bring up our knowledge of the anatomy of the Parrots to a higher level than that of many other groups of birds ; the facts accumulated in the papers referred to will at any rate serve some one w h o can supplement them by the observation of other genera with a mass of information upon which a definite scheme can be made out. In the meantime, however, w e may indicate a few questions of affinity as to which our investigations appear to throw some light. In the first place, there is the remarkable genus Stringops : there is no doubt that its purely terrestrial habits have led to some degeneration; it has, for example, a flat sternum; but degeneration of this kind would hardly be expected to affect such organs as are treated of here with the exception, of course, of the muscles of the patagium. It is perhaps a noteworthy point that on the whole the musculature of the arm as far as we have studied it is like that of Nestor, a Parrot which of course occurs in the same part of the world; the agreement as to these muscles also extends to Calyptorhynchus, in which genus the syrinx also is fashioned after the plan characteristic of Stringops : this is also of importance ; these two genera are, from our point of view, the nearest allies of Stringops, which does not, in so far as the facts treated of here have weight, occupy nearly so isolated a position in the system as has been assigned to it by others2. To a great extent, therefore, our results bear out Prof. Garrod's 1 Bronn's Klassen u. Ordn. d. Thierreichs, Aves, p. 18. 2 E. cj. in M r . Sclater's classification used in the " List of Animals." Fiirbringer (J. f. O. (4)xxxvii. p. 241) puts Stringops down as a primitive, if not the most primitive, Parrot. |