ANATOMY OF THE SHOE-BILL. 687 



group. He was disposed, howevei% to attach value to the loss of 

 any of these muscles, and accordingly regarded the loss of this or 

 that muscle as one of the charactei'S to be employed in judging of 

 the relationships of groups. Even this cautious use seems to me 

 to be going too far. At present I do not know of any i-eason 

 why we should suppose that a particular muscle may not have 

 been lost independently many times ; that is to say of any reason 

 why a bird that has lost its femoro-caudal muscle should be more 

 nearly related to another bird with a similar loss than to a bird 

 which has retained the possession once common to all three. The 

 loss is what I have described as a multiradial apocentricity. 

 Possibly when we know as much of the development and mor- 

 phology of the muscles used by Garrod, as Fiirbringer has taught 

 us iij- the case of the shoulder and wing muscles, we shall be able 

 to make more definite use of muscular anatomy in systematic 

 ornithology. As, however, muscular anatomy has been used 

 freely, I may give a summary of the chief facts from which more 

 confident anatomists would di'aw inferences. 



Comparison of Herons, Storks, Scopus and Bcdceniceps. 



Peculiar to Bcdceniceps. 



Absence of latissimus dorsi metapatogialis. ("? S'cojms.) 



Absence of humeral head of biceps brachii. (Unique.) 



Absence of deltoides minor. (^ Scopics.) 



Absence of teres minor. C^ Scopus.) 



Origin of serratus superficialis posterior confined to dorsad of 



uncinate processes. (Same in Fhcenicopterus.) 

 Accessory oi'igin from tip of scapula of serratus metapatagialis. 



Common to Bcdceniceps and Scopus. 



Condition of deltoides patagialis and patagial tendons. 

 Expansor secundariorum vestigial or absent (so also in most 

 Steganopods). 



Common to Bcdceniceps and Herons. 

 Presence of peroneus profundus. 

 Arabiens reduced to a distal vestige (said to be absent in 



Scojncs, pi-esent in Stoi-ks). 

 Deep flexor tendons. 



Conunon to Bcdceniceps and Stoi-ks. 



Peculiar arrangement of tendon of insertion of latissimus 



dors. post. 

 Practical doubling of pectoralis major (also in some Steganopods). 

 Presence of post-acetabular portion of glutteus maximus (at 



least in some Storks ; ? Scopus). 

 Oval origin of obdurator internus (also in most Steganopods). 



Common to Bcdceniceps., Scopus, Herons, Stoi'ks and most Stega- 

 nopods (but also in many other groups). 

 Absence of biceps slip to patagium. 

 Absence of accessory femoro-caudal. 



