344 



TEE MUSCLES. 



Preparation. — 1. Place the animal on its side, or, better, in the second position. 2. Remove 

 the skin from this region in order to show the gluteal apoueurosis, and to study its extent, 

 attachments, and relations. 3. Cut away this aponeurosis to expose the anterior point of the 

 middle gluteus 'and the muscular portion of the superticial. To prepare the apoueurotic 

 portion of the latter muscle, the sacro-sciatic insertion of the long vastus must be detached by 

 the scalpel and thrown downwards. 4. Incise the superficial gluteus near its femoral insertion, 

 and reverse it on the sacral spine, so as to lay bare the external face of the middle or principal 

 ^duteus. 5. Divide this muscle near its femoral insertions, taking care not to inj ure these, and 

 remove the whole of its mass, studying raeanwhUe the nature of its relations to the parts 

 it covers; the deep or small gluteus then becomes apparent, and may be conveniently 

 examined. 



To render the dissection and study of these muscles easier, the hind quarters may be 

 arranged as in Fig. 192. A special upright support passes between the last ribs, and a 

 horizontal lever maintains the lumbar region fixed in a kind of metallic fork. By this 



arrangement the croup and hips are 

 Fjg. 192. kept in a good direction, the mass 



I/, ^ ^ C I being made tense, so that they can 



be dissected nearly in their normal 

 relations. 



1. SupEEFiciAL Gluteus 

 (Gluteus Exteenus) 

 (Fig. 193, 2, 4). 



Synonyms. — Ilio-trochanterius 

 medius — Girard. Gluteus minor 

 — Boxirgelat. Gluteus medius — 

 Rigot and Lafosse. The gluteus 

 magnus of Man. (^Ilio-trochanterius 

 externus — Leyh.) 



Coinposition — Situation . — 

 This muscle is composed of 

 two portions— one anterior, 

 the other posterior, closely 

 joined, and situated beneath 

 the gluteal fascia. They form 

 the most superficial portion of 

 the fleshy masses of the croup 

 and inner face of the thigh. 



Form — Structure — Attach- 

 ments. — A. The anterior 'por- 

 tion (the mperflcial or middle 

 gluteal muscle of veterinary anatomists) comprises a muscular and an aponeu- 

 rotic division. The first is triangular in shape, deeply notched in its upper 

 border, so that it is sometimes divided into two parts — an external and an 

 internal. Its fasciculi are very thick and loosely united ; they all pass back- 

 wards and downwards, to converge in a flattened tendon which terminates the 

 inferior angle of the muscle. The aponeurosis, also triangular, is confounded 

 in front with the posterior border of the muscular portion and its terminal 

 tendon, and is insinuated behind, beneath the posterior portion ; it degenerates 

 into connective tissue at its inner and upper border. The anterior part of the 

 muscle has it?, fixed insertion : 1. On the internal aspect of the gluteal aponeu- 

 rosis, by the superior extremity of its muscular fasciculi. 2. On the postero- 

 external angle of the ischium, and the sciatic ligament, by the internal border 

 of its aponeurotic portion. It has its movable insertion, by means of its terminal 

 tendon, on the small external or third trochanter of the femur. 



T, Table ; A, showing the principal support ; B, posterior 

 horizontal bar ; C, blunt point at the end of the branches 

 of the T placed at the extremity of the posterior branch; 

 D, anterior horizontal branch terminated by vertical 

 branches, E, on which the last pair of ribs rest ; L, 

 notched lever which keeps the animals hind quarters on 

 the support ad hoc. 



