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Show 706 MR. F. G. PARSONS ON THE [June 16 ficial and deep divisions of the anterior crural nerve. A little lower down an internal circumflex comes off, which divides into a large transverse and a small ascending branch. The femoral artery then continues down Hunter's canal, but no profunda femoris is given off. At the low^er part of the canal it divides into two large branches, of which the anterior accompanies the internal saphenous nerve to the inner side of the leg. A little above the internal malleolus it divides into anterior and posterior, the former passing in front of the malleolus and deep to the tendon of the tibialis anticus, to supply the inner side of the dorsum of the foot the latter supplying the sole of the foot, though no distinct external and internal plantar arteries are present. The posterior of the two branches of the femoral in Hunter's canal is the popliteal, this passes between the semimembranosus and the femur, and divides into superficial and deep. Tbe superficial is a muscular branch to the calf-muscles and runs down between the gastrocnemius and plantaris. The deep passes deeply to the plantaris, pierces the interosseous membrane to become the anterior tibial, and runs down along the outer side of the tendon of the extensor longus digitorum to the dorsum of the foot, the outer side of which it supplies. As soon as it reaches the commencement of the dorsum it gives off a communicating branch which passes superficial to the extensor longus digitorum to join the anterior branch of the internal saphenous artery already mentioned. The Interned Iliac artery divides into gluteal, pudic, and sciatic, of which the last is the largest. The Veins correspond fairly accurately with the arteries, the chief points worthy of notice being the large size of the external jugular, the presence of two anterior and a single undivided posterior venae cavae, also of a single azygos vein, which lies on the right side and receives the intercostal veins from both sides of the thorax. The Nervous System. As the animal was not received in a perfectly fresh condition, I made no attempt to examine the brain and spinal cord. The Cranial Nerves differ but slightly from those of Man: the chief points of divergence noticed are:-(1) That the seventh nerve only divides into three chief branches on the face; (2) that the depressor nerve is separate from the vagus and comes off from the superior laryngeal as in the Babbit; (3) that the eleventh nerve pierces the cleido-mastoid after supplying the sterno-mastoid and then passes on to the trapezius ; (4) that there is no descending branch from the hypoglossal corresponding to the descendens cervicis of human anatomy, but the omo-hyoid, sterno-hyoid, and sterno-thyroid are supplied by a well-marked nerve which comes off from the 1st and 2nd cervical and corresponds to the com-municans cervicis. The Cervical Plexus is formed by the first four cervical nerves; there is the usual loop on the ventral side of the transverse process |