MUSCLES IN ISIHUS. 313 



The external pluntar region likewise comprises throe muscles, which arc : 



1. The fhttrt itlidui'tur of tin' little, toe, which is d> tach.-d from the internnl tulx-rosily 

 of tin- o> c.dci>. mill is iiiM-rtcd into tin- external jorti"n of tlie first phalanx of the little 

 toe. 



2. The short flexor of tin- littli t< e is attached, behind, to the shenth of the long 

 IXTOIICHS 1U id to the process of the fifth metatarsal ; in front, to the external part of the 

 first phalanx of the littl<- toe. 



3. The opponent of the little toe, concealed beneath the preceding, is inserted at 

 one end to the sheath of the long peroneus, and at the other to the external border of 

 the tit'tli mctutarsnl. 



C. [nterosseoua Muscle*. 



These are divided into dorsal and plantar interossei. Their disposition is nearly 

 the same as in the hand. 



CHAPTER in. 



THE MUSCLES IN BIRDS. 



IN birds we find the majority of the muscles already described ; thougli they are appro- 

 priate by their form, volume, arrangement, etc., to the particular conformation of the 

 skeleton in these animals. 



To undertake, in this essentially practical work, a special description of all these 

 organs, would be to depart from the object aimed at : and we therefore confine ourselves 

 to those points which present most interest in an animal mechanic point of view. 



1. Tendons The tendons in birds present in the inferior limbs and at the extremity 

 of the wings an amount of ossification more or less extensive along their course. This 

 transformation of the fibrous tissue of the muscles is not the effect of senility, for it ifl 

 noticed in very young animals. 



The tendons, in losing the greater part of their elasticity, doubtless gain in tenacity ; 

 and this allows them to transmit to the bony levers the muscular efforts in a more 

 integral manner. 



It is also observed that the partial ossification of the tendons does not exclusively 



belong to the limbs ; for it is not rare to meet with this change in other regions, as in 



tin- n.-ck of wH>ling birds. In the museum of the Veterinary School at Lyons is the 



>n of a heron which shows this peculiarity in the highest degree; the cervical 



rte are roughened by a multitude of filiform bony stylets, all directed backwards, 



and which have originated from the ossification of th*e tendinous fibrilhe annexed to the 



inn- 1 region. 



J '//- rtral Muscles. The two alternative movements which produce flight the 

 elevation and .|I-J,M .-.-i-m of the wings being due to the action of the pectoral muscles, 

 these merit .-]>. -ial notice. 



Tin fuiHTjl'-iitl or <irit jwctoral, " which alone weighs heavier than all the other 



inii-'l. - ! tin- !>irl put I"-, tli- r. U attached to the fnn-nlum. to the great ridge of the 



bt- riniiii, and to tin lust ribs; it is inserted into the very salient rugged outline of iln- 



hum-Til.-. It is by this niu->d-- that birds are able to give those powerful strokes of the 



I whi'-h are necessary in flight." 



Tin- d't-ji or umaU pectoral is " placed in the angle forme*! by the body of the sternum 



and its cre.st. and in tin- interval Ix-tw.-en tin- fnn-iilum and the coracoid bone. 



Its tendon passes through the foramen formed by the union of tin- furculum, the coracoid 



I ioiie, and the scapula, as over a pulley ; it is inserted above the head of tin hum. ru-, 



whieh it raises. It is by means of this arrangement that nature has U--n able to pla 



.ut'ir and d. j, r .-.-s..r at the inferior surface of the trunk so far from the centre <( 



gravity, without which the liird would have been liable to lose ita equilibrium and tumble 



head foremost in the air. 1 



Ciuier, adopting the nomenclature of Vic.| d'A/vr, called this muscle the middle 



/, and h<^ gave the name of small pectoral to a triangular f..x-iculns which leaves 



the lateral angle of the sternum and the base of the coracoid l'iie, to bo inserted under 



1 Cuvier, ' Leom* d Anatomic O>m| are. ' 



