the left; both lie on the inner border of the corresponding psoas muscle, and are crossed by the spermatic vessels and the ureter; the vessel of the left side has also in front of it, the inferior mesenteric artery, and the sigmoid flexure of the colon. The iliac veins are found internal to, and on a lower plane, than their companion arteries, and their junction is effected beneath the upper part of the right iliac artery. Both vessels are covered by the muscles of the anterior abdominal wall, and lie behind the peritoneal cavity and small intestines. A line drawn from the left side of the navel to the centre of Poupart's ligament on either side, pretty nearly indicates the direction of the course they pursue. To apply a ligature to this vessel, divide the integuments to the extent of five inches, beginning at a point an inch below and two inches nearer the middle line than the anterior spine of the ilium, and extending from this point upwards with a slight inclination outwards. The three abdominal muscles must be recognised and separately divided, and the fascia transversalis cautiously cut upon the director; the subperitoneal fat ought now to be seen, and from this stage of the operation the knife should be abandoned. An assistant should hold open the wound, while the operator raises the peritoneum and its contents with his left hand, pushing it upwards and inwards, and separating it from the iliac fossa with the point of the director, until the psoas muscle is reached. Immediately internal to this muscle, at the posterior part of the pelvic brim, the artery will be found; its connections being detached to a small extent, the aneurism needle, which should be of a suitable shape, may be passed from within outwards, as this best secures the safety of the corresponding vein.

Little thought need be bestowed, during the operation, on the spermatic vessels and ureter, as they generally rise

with the peritoneal sac, and adhering to its under surface, are scarcely observed.

We have described this operation as if performed on the right side of the body: on the opposite side its difficulty is increased by the presence of the sigmoid flexure of the colon, which crosses the vessel at its bifurcation, and must be raised before a ligature can be applied.

The internal iliac artery, leaving the common iliac at the sacro-iliac joint, runs downwards and forwards towards the great sciatic notch; it is crossed in front by the ureter descending into the pelvis; behind the vessel is found its corresponding vein with which it is generally pretty closely connected. The same operation is necessary for the ligature of this vessel as was described for the common iliac; the artery, however, must be sought below the pelvic brim, and great caution will be required to clear it from the veins which often unite on its inner side.

The external iliac artery extends from the sacro-iliac joint to the centre of the crural arch; following the brim of the pelvis for some distance, it lies to the inner side of the psoas muscle, and has its own vein internal to it, but on a lower plane. Just before its termination, this vessel is crossed at right angles by the circumflex ilii vein, and obliquely, about the middle of its course, by the genitocrural nerve it lies behind the peritoneal sac and small intestines. This vessel may be tied at any part of its course; we shall select a part of its trunk, about two inches above Poupart's ligament, as this is a sufficient distance from the origin of its branches, the epigastric and circumflex iliac.

Operation.-Make an incision about three inches in length, beginning at the centre of Poupart's ligament, and half an inch above it, running in a slightly curved direction, outwards and upwards towards the anterior superior

spine of the ilium. Divide separately the external oblique, the internal oblique, the transversalis and fascia transversalis. The subperitoneal fat having been exposed, push the peritoneum upwards and inwards, and search for the artery on the inner margin of the psoas: it may be easily cleared from its connections, and a ligature applied from within outwards. In this operation the connections of the peritoneum need only be disturbed to a very small extent.

The femoral artery.-From the crural arch, this vessel extends down the inner side of the thigh, to the opening in the adductor magnus muscle; its course is indicated by a line drawn from the centre of Poupart's ligament to the most prominent point of the inner condyle of the femur.* In the upper third of its course this artery has the femoral vein to its inner side for a short distance, and the anterior crural nerve on the outer side; it is here covered by nothing but the integuments, superficial and deep fascia, and its own sheath.

The middle third of the femoral artery has its companion vein behind it; and on the outer side, or in front, is the long saphenous nerve; it is covered by the sartorius muscle, in addition to the integuments and fascia of the thigh. The vessel here lies between the vastus internus on its outer, and the adductor longus on its inner side.

In the lower third of its course the femoral artery is found at the angle of meeting of the vastus internus and adductor longus; in front it is covered by the fascia forming Hunter's canal, which latter is overlapped by the sartorius.

This artery may be tied in any part of its course; we shall therefore describe the ligature of the vessel in its upper, middle, and lower thirds.

Upper third.-The limb being abducted, make an incision two or three inches in length, in the direction of the

*The point that gives insertion to the tendon of the adductor magnus.

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line leading from the centre of the crural arch, to the prominence of the inner condyle; divide the superficial fascia, fascia lata, and sheath of the vessel, clear the artery, and pass the ligature from within outwards.

Middle third.-Divide the integuments in the direction of the line before mentioned and to the same extent; after laying open the superficial and deep fascia, the sartorius will come into view; this being pushed outwards, lay open the sheath of the vessel and pass the ligature between the long saphenous nerve and the artery. There is occasionally a branch of the middle cutaneous nerve lying over the artery at this part of its course, which one should avoid injuring, though practically its division would be of but little con

sequence.

Ligature in Hunter's canal.-An incision should be made in the line of the artery, commencing about the middle of the thigh and extending downwards for three inches. After dividing the superficial and deep fascia, the sartorius will generally be seen, and this must be drawn to the inner side. The first finger should now be passed down the adductor longus towards its insertion into the linea aspera of the femur, until the point of the finger rests against the vastus internus, at the spot where it is blended with the former muscle. Carefully lay open the fascia which connects these two muscles, and separate the artery, which will now be seen, from the vein and long saphena nerve. Pass the ligature from within outwards, taking care that the vein which lies behind be not included, adhering as it does very firmly to the artery.

There is often considerable difficulty experienced in exposing the vessel in Hunter's canal, and this generally arises from one of two causes; namely, either the first incision is made too low down in the thigh, or the line of the vessel, before mentioned, is not correctly ascertained

before commencing the operation. To avoid the inconvenience of turning the body, we shall omit for the present the ligature of the popliteal artery, and proceed to describe the operation for tying the anterior tibial.

The anterior tibial artery, entering the front of the leg through the interosseous membrane, beneath the head of the fibula, continues its course down the limb, to the first interosseous space on the dorsum of the foot. It lies successively on the interosseous membrane, the tibia, the front of the ankle joint, and over the astragalus, the scaphoid, and the internal cuneiform bone. In the upper third of the leg it is found deep between the tibialis anticus and the extensor longus digitorum; below this it lies between the former muscle and the extensor of the great toe, and on the dorsum of the foot it intervenes between the extensor proprius pollicis and the innermost tendon of the extensor longus digitorum. In front of the ankle joint the artery is crossed from without inwards by the long extensor of the great toe, and on the dorsum of the foot by the first tendon of the extensor brevis digitorum.

A line drawn from below the inner side of the head of the fibula, or rather from the centre of the muscular space between the heads of the tibia and fibula, to a point midway between the maleoli, indicates the course of this artery. The vessel in question is approached in any part of the leg through the innermost intermuscular space, the exact seat of which is indicated by a white line in the fascia, just external to, and nearly parallel with, the spine of the tibia. The artery can be tied in any part of its course; we shall describe the measures necessary for exposing it in its upper, middle, and lower thirds.

Ligature in the upper third.-An incision, three inches in length, should be made over the artery in the line of its course, beginning an inch below the head of the tibia; the