208 



being weak but functional ; all the toes are furnished with very 

 short nails. But for the bare distal portion of the leg, and the 

 presence of the hallux, the whole foot of Fedioitumus closely 

 resembles that of the Turnices and differs from that of the Rasores 

 although its intermediate position between a ^;es cursorius and a 

 pes radeiis is obvious. 



Ahiscular System. 



The muscles of the hindlimb afford some interesting points. 



Garrod's formula for the Rasores is A B x y + , meaning tliat 



these birds retain the primitive condition in which besides others 



the following muscles are present : — 



+ = M. ambiens. 



A = Femoro-caudal muscle, i.e. pars caudalis m. caud-ilio- 



femoralis. 

 B = Accessory femoro-caudal, i.e. pars iliaca m. caud-ilio- 



femoralis. 

 X = Semitendinosus i.e. the tibial insertion of the m. caud- 



ilio-flexorius. 

 y = Accessory semitendinosus, i.e. the femoral insertion of 

 the m. caud-ilio-flexorius. 

 In a few of the Rasores, viz. in Pavo and Meleagris, and in a 

 few other birds e.g. in Podiceps, Otis, Dicholophus, Serpentarins, 

 Pliuiiticopterus, (fee, the caudal portion of the m. caud-ilia-femoralis 

 is absent, the formula being B x y. In the Turnices on the other 

 hand the iliac portion of this muscle is absent; consequently A x y. 

 In PedioiiOhius both poi'tions are present, but while the iliac por- 

 tion is very broad and is inserted nearly along the whole length 

 of the femur, the caudal jDortion is an extremely thin and feeble 

 slip which comes as a mere thin tendon from one of the caudal 

 vertebra?, and can scarcely be traced as an independent slip beyond 

 the pubis, where it practically disappears and merges into the iliac 

 portion of the muscle. The formula for Pedionomus is therefoi'e 

 A B X y as in most Rasores, and if the reduction of A were con- 

 tinued, Pedioii07nus would have the same symbolic formula as 

 Pavu, Meleagris, viz. Bxy. Certainly there is no resemblance 

 between Pedioiiomus and Tur'iiix in this respect, but it would be 

 very rash to conclude that Pedioiioniiis is allied to the Rasores 

 because of this formula. On the conti-ary we have to conclude 

 that Pedioiioimis still retains partly tlie primitive condition, and 

 that the reduction of the muscle A is due to the same unknown 

 causes which have eliminated it in Pavo and in Meleagris, in Podi- 

 ceps, Otis, Dicholup)lius, Serpentarius, and in Plivenicopterus, i.e. 

 in birds which prove that the absence or presence of this muscle 

 can be only of very little taxonomic value. 



Fuerbringcr's Table xl?«. u. contains sevei'al otliei' myological 

 characters, Nos. 30 - 42 of occasional taxonomic value, but they 

 are not suitable for the solution of the question if Pedioitomus is 



