1891.] ANATOMY OF THE KAGU. 19 



Gadow, 16, plate xxiii. a. fig. 7), arises from the deep flexors ; 

 in Nycticorax the muscle was attached to the tendons of both 

 flexors. It would be worth while to inquire into the relations between 

 the muscle and the vinculum, since there are cases of the conversion 

 of muscles into ligaments among birds ', among which I may mention 

 the ligament in the Hornbills representing the glutseus maximus 

 of other birds ^. In Ardetta exilis and A. involucris there is no 

 vinculum (Forbes, MS.). 



(15) The attachment of the flexor tendons to the phalanges varies 

 slightly in different birds. 



In the third toe the tendons of the flexor perforatus and the 

 flexor perforans et perforatus are joined by a short ligament not far 

 in front of the insertion of tiie first on to the digit ; there is no such 

 connection in the case of the same tendons supplying digit ii. 

 Digit IV. has of course, like all other birds, no flexor perforans et 

 perforatus. 



The branches of the flexor profundus run to the last phalanx of 

 each digit to which they are attached ; but during their course they 

 also give off branches to other phalanges ; in the second toe the 

 tendon is attached not only to the last but to the penultimate 

 phalanx. The same additional insertion is present in digits iii. and 

 IV., but the ivth digit has a third attachment close to where the ten- 

 don perforates the tendon of the ^mw perforatus; in. digits iii. 

 and IV. there are several thin branches placed just behind the final 

 insertion of the main tendon. 



Affinities of Rhinochetus. 



Tiie original describers of this bird, MM. Des Murs and Verreaux 

 [1], placed it definitely with the Ardeidse ; their opinion was based 

 upon the general coloration : the powder-down patches which cha- 

 racterize this bird, and are to a certain extent evidence of its affinity 

 with the Ardeidae, were not mentioned ; the presence of these was 

 first noticed by Mr. Bartlett. 



The arrival of a specimen at the Society's Gardens in 1862 

 enabled Mr. Bartlett to study the habits of Rhinochetus [3] ; he 

 mentions that its movements are lively and quick, and not slow like 

 those of a Heron ; its mode of feeding and its food (snails, earth- 

 worms) differ from those of the Herons ; it is compared with Eu- 

 rypyga and regarded as Ardeine. 



In 1866 Mr. Bartlett described the esrs, which is blotched like 

 that oi Eurypyga and the Cranes, and quite unlike the Heron's pale 

 green egg witfci no markings ; again, the lively movements are those 

 of a Crane rather than of a Heron. 



Prof. Parker, in his 'Monograph upon the Shoulder-girdle,' united 



^ This matter has been gone into by Mr. J. Bland Sutton, P.E.C.S., in his 

 interesting work ' Ligaments, their Nature and Morphology.' 



^ Dr. Gadow, in his work on Birds (Bronn's ' Thierreichs'), has mentioned 

 thi? ligament in Bucorvus. It exists in other Hornbills. 



2* 



