240 



TEE MUSCLES. 



Without this precaution, the various parts of the body may assume an inconvenient siiape oi 

 direction, and all attempts to amend them will prove almost unavailing, particularly in the 

 larger animals. 



Three principal positions may be given to subjects: 



1. The animal is in the first position when it is placed on its back, the four extremities in 

 the air, and maintained in that posture by means of long cords passed round the pasterns, and 

 fixed to the movable rings which terminate the extremity of the four bars of the wheeled table 

 on which the subject is laid. The head should be beyond the end of the table and rest upon a 

 stool. The animal should always be placed in such a manner that the head be opposite the 

 fore-part of the table, so that the movements of the pole or shaft be not impeded during the 

 displacement of the apparatus In order that the neck be not twisted to the right or left, in 

 attaching the fore limbs the subject .--hould be raised so that the withers rest lightly on the 

 table. According to the bulk of the animal and the length of the bars, the ropes should be 

 passed around either the pasterns, above the fetlocks, or even aViove the knees (Fig. 156). 



2. To place the animal in the second position, it is turned on the belly, the two thighs 

 flexed, the extremities carried beyond the table, and the head fixed between two bars by means 



Fig. 156. 



HORSE FIXED IN THE FIRST POSITION ON ONE OF THE WHEELED TABLES IN USE AT THE 

 LYONS VETERINARY SCHOOL. 



of a rope passed under the zygomatic arches; or better, two coids with metal hooks may be 

 employed, a hook being tixed into each orbital arch, or through the skin and masseter muscle 

 to beneath the zygomatic arch, the cords being tied short to the uprights of the talde (Fig. 

 157). A block of wood or small stool may be employed to prop the trunk by placing it in the 

 sublumbar region (Fig. 157). 



3. The subject is in the third position when it rests on its side. 



Rules to be observfd during the prepardtion. — 1. By no means, if possible, remove the skin 

 from the regions to be dissected until quite ready to begin the dis-ection. If this is impossible, 

 then take the precaution of enveloping these regions in damp cloths, or in the animal's skin, 

 to prevent desiccation of the aponeuroses and the superficial muscles. 



2. To dissect a muscle, it is necessary to remove the aponeuroses or the other muscles which 

 cover it, the connective tissue enveloping it, and the fat, glands, vessels, and nerves lotlged m the 

 neighbouring interstices. The aponeuroses should be removed in shreds by mukina: them very 

 tense with the forceps, but without mising them, and causing the blade of the scalpel to glide 

 between the fibrous and muscular surfaces, keeping it always parallel to these two planes. The 



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