Summary: The lumbrical and interosseous muscles in twenty-five feet of Japanese adult cadavers were dissected. The lumbrical muscles mainly continued into the dorsal aponeuroses or the terminal tendons of the extensor digitorum longus muscle, though they occassionally issued some accessory and slender tendons inserting into the bases of the proximal phalanges. Rarely, the lumbrical muscle showed an atavistic anomaly. In this anomaly, the lumbrical muscle was divided into two tails which continued into the bases of the proximal phalanges of the contiguous toes. The plantar and dorsal interosseous muscles were mainly attached to the bases of the proximal phalanges. Frequently, the plantar and dorsal interosseous muscles issued some accessory and small tendons continuing into the dorsal aponeuroses.This fact suggests that the plantar and dorsal interosseous muscles in the foot, like the palmar and dorsal interosseous muscles in the hand, are composite muscles derived from the flexor brevis, contrahens and other muscles.The lumbrical muscles of the human foot are generally regarded as being inserted into the proximal phalanges (Henle, 1871; Frohse and Frãnkel, 1913; Paturet, 1951;Mortenson and Pettersen, 1966;Gardner, Gray and O'Rahilly, 1971; Tillman and TOndury, 1987). However, our recent dissection of Japanese feet has revealed that the lumbrical muscles mainly end in the dorsal aponeuroses. These are reported in the present paper. The insertions of the interosseous muscles are also described and discussed in relation to their phylogenetic compositions. Materials and MethodsTwenty-five feet of Japanese adult cadavers of both sexes, which had been fixed with 10% formalin by vascular perfusion and dehydrated with 60-70% ethanol, were dissected with sharpened forceps under a dissection light microscope. ResultsThere were four lumbrical, four dorsal interosseous and three plantar interosseous muscles in the human foot (Fig. 1, 2, 3). These muscles were numbered from the medial side of the foot (Figs. 1, 2, 3). No morphological difference of the lumbrical, dorsal interosseous and plantar interosseous muscles was observed between the male and female cadavers and also between the right and left feet.The dorsal aponeurosis of the toe consisted of the tendons of the extensor digitorum longus and brevis muscles and the outer and inner tendinous membranes arising, together with the deep plantar metatarsal ligaments, from the plantar aspect of the neck of the metatarsal bone (Figs. 4, 5, 6). The inner tendinous membranes ran around the neck of the metatarsal bone, and enclosed the tendons of the extensor digitorum longus and brevis muscles at a level between the neck of the metatarsal bone and the head of the proximal phalanx (Fig. 5). Thus, the inner tendons extended bilaterally along the proximal phalanx (wing tendons) (Figs. 4, 6). The outer tendinous membrane was thick and band-like, and firmly surrounded the plantar and dorsal interosseous muscles and the enclosed tendons of the extensor muscles (see above) (Figs. 5, ...

Summary. Blood vascular casts of the rat adrenal glands were observed with a scanning electron microscope. The cortical capillary plexus drains, through the corticomedullary venous radicles, into the subcortical veins continuous with the medullary collecting veins. The medullary capillary plexus drains into the corticomedullary venous radicles, subcortical veins and medullary collecting veins. No portal vessel was noted between the cortical and medullary capillaries. These findings indicate that the cortical blood rich in glucocorticoids preferentially and continuously flows into the corticomedullary venous radicles, subcortical veins and medullary collecting veins all three of which are fenestrated in type, and also suggest that the vascular route from the cortical capillaries to the medullary collecting veins functions as a substitute for the portal system, controling the biosynthesis of catecholamines in the adrenal medulla. The vascular bed of the accessory adrenal gland (extra-adrenal cortical or chromaffin body) is sometimes annexed to that of the adrenal gland. On rare occasions, the vascular beds of the extra-adrenal cortical and chromaffin bodies fuse with each other. Additional scanning of tissue samples confirmed the direct drainage of cortical capillaries into the medullary veins and also the endothelial fenestrations of these capillaries and veins.

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