1893.] THE AJTATOMY OF P.UlllOTS. 513 



Gadow ^ describes the peroneus longus as apparently' absent in 

 Chrysotis. 



In the other genera examined the muscle is intermediate between 

 Strinrfops and ChnjsoUs ; it rises from about the middle third of 

 the leg as higb 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 sur- 

 rounds the deep flexor tendons opposite tlie 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 

 CJinjsotis, 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 classitieation 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 ; and in 

 the second place we 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, com- 

 bined 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 who 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, we may 

 indicate a few questions of affinity as to which our investigations 

 appear to throw some light. In the first place, there is the remark- 

 able 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 patagiura. It is pei'haps a noteworthy 

 point that on the whole the musculature of the arm as far as 

 we have studied it is like that of JS^estor, a Parrot which of course 

 occurs in the same part of the world ; the agreement as to these 

 muscles also extends to Calij2ytor7iync7ius^ in which germs 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 others ^. 



To a great extent, therefore, our results bear out Prof. Garrod's 



^ Uronn's Klassen u. Ordn. cl. Thierreichs, Aves, p. 18. 



^ E. g. in Mr. Sclater's classification used in the " List of Animals." Fiir- 

 briiiger (J. f. O. (4)xxxvii. p. 241) puts Stringops down as a primitive, if not the 

 most primitive, Parrot. 



