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Show 670 MR. F. E. BEDDARD ON BASSARICYON ALLENI. [June 19, to it. The chief facts about its origin to be noted are that it does not extend back as far as the ilium, and that part of its origin is from tbe last three ribs ; it joins the teres at insertion which forks over the head of the biceps. The Trapezius presents no particular features of interest; it is attached largely to nearly the whole length of the spine of the scapula; and there is also the cephalo-humeral portion which passes down the arm but is inserted on to the humerus as in other Arctoids. The Omotrachelian is of course present and attached just in front of the last-mentioned muscle. The Dorso-epitrochlear is slender and strap-shaped. The Deltoid calls for no special remark. It is composed of two portions as in other Carnivora (not counting the cephalo-humeral). The Triceps consists of four distinct portions which can be .referred to this muscle, and possibly of a portion whose nature is somewhat doubtful and with which we shall deal presently. The two outer heads are thick muscles which blend with each other not very far from their insertion on to the elbow. Their origius are concealed by the two divisions of the deltoid. The posterior of the two arises from the margin of the scapula near to' the glenoid cavity. The origin of the anterior is from the head of the humerus. These two divisions are superficial to a deeper stratum of the triceps. This latter consists of the two portions that appear to exist in other Carnivora. Of these one arises just under the anterior superficial head and joins about halfway down the humerus the fourth head, which arises from the upper part of the shaft of that bone. A broad slip of muscle, which appears to correspond to the second dorso-epitrochlear of some authors, arises superficially from the tendinous junction of the latissimus dorsi and the teres major, and therefore considerably above the origin of the undoubted dorso-epitrochlear. It is a flat strap-shaped muscle, and is inserted much nearer to the elbow-joint than the dorso-epitrochlear. The Anconasus is a fleshy mass arising from the lower half of the humerus, and inserted on the same level as the deep portion of the triceps. The Epitrochleo-anconceus was found. Tbe Supinator longus is present, as in all Arctoids and the majority of the Carnivora. The Extensores carpi radiates longior et brevior are completely blended and indistinguishable at their origin. Concerning the Extensor carpi ulnaris, Extensor communis digitorum, Extensor minimi cligiti, I have no remarks to offer. The Extensor digitorum profundus arises from the dorsal surface of the ulna only. The Extensor ossi metacarpi pollicis arises as in other Carnivora from both radius and ulna. The Pronator radii teres appears to have an exceptional arrangement in Bassaricyon. As a rule in this group of Arctoids the |