66 Appendix. 



In the Macrocbires, iududing tlie Trochilidae and the Cypselidae, as found in many genera 

 and species, the aiTangement is uniform. The fleshy belly runs on to a special tendon which 

 springs from the lower end of the outer surface of the humerus (where the horizontal slij) in the 

 Passeres terminates), and is continued, parallel to the forearm, along the radial margin to the 

 band. The tendon of the tensor jiatayii hrevis is not developed, being replaced by the fleshy 

 continuation of the muscle. 



In Upupa epo-ps the arrangement is faii-ly simple. The main tendon runs past the free 

 lateral margin of the long extensor to the ulnar superficial fascia, where it becomes lost. It sends 

 forward a fasciculus from about its middle, to end like the similar band in the Meropidae. Its 

 difference from the passerine arrangement is well marked. 



In the Bucerotidae, as found in several species of Buceros, Toecus, and Bmorvus, the only 

 difference from Upupa is that the extra outer fasciculus is very much shorter. The lengthy tendon 

 from the major pectoral is particularly large. 



In the Alcedinidae the differences are so considerable and peculiar in the several genera 

 that the muscle in this order has not been fully worked out as yet. 



In the Momotidae the condition is the same as in the Coraciidae, except that the outer 

 tendon does not split, and therefore sends forward no wristward slip. This condition I have 

 found in Momotus lessoni, in M. aequatorialis, in Eumoinota superciliaris, and in Tidus viridis. 

 The extension onwards to the ulnar superficial fascia springs from the portion of the horizontal 

 tendon intermediate between the points of junction of the two parallel long tendons, and is not 

 a direct continuation of either. It is frequently very thin. 



As the Cuculidae and Musophagidae are frequently included together with the families 

 above referred to, the arrangement of the short tensor in these birds must be mentioned. In 

 all the Cuculidae the undivided tendon runs on to the ulnar superficial fascia without any com- 

 plication. In the llusophagidae the whole tendon is comparatively feeble, and, if it were more 

 definite at its margins, would be exactly like that in Upupa. 



Next, with reference to the division of the order Passeres into minor sections. 



In 1831 the late Professor C. J. Sundevall discovered the important fact that is expressed 

 in the 1872 edition of his valuable ' Methodi naturalis Avium disponcndarum Tentameu' in the 



following words : 'Hallux per se mobilis. Musculus euim_^«a;o?- /iaZZwrn- fo»//Hs articulum 



ejus ultimum flectens, a flexore digitorum coinmuni perfecte solutus. (In avibus rcliquis omnibus 

 tendo hujus musculi cum tendinibus alterius conjungitur. Hallux igitur simul cum reliquis digitis 

 semper flectitur.)' Upupa epops, agreeing with the Passeres in this respect, is by the author 

 included with them. Recently, however, I have found reason for overthrowing the character, 

 because iu the Eurylaemidae there is a strong vinculum which joins the two muscles exactly in the 

 same manner as in many of the non-passerine families. 



Eurylaemus ochromelas, Cymhirhijnchus macrorhynchus, and Calypiomena viridis arc the 

 species which I have examined (more than one specimen of each) ; and in all of them there is 

 a narrow but strong vinculum, situated just above the metatarso-phalangeal articulations, and 

 ranning from the tendon of the Jlexor hallucis loncjus downwards to the tendon of the flexor 

 dkjitorum profundus. No other passerine bird which I have dissected possesses this vinculum, 



