162 



HISTOLOGY 



suggesting an encysted foreign body. The axial core of the corpuscles 

 is surrounded by concentric layers, sometimes as many as fifty, which 

 represent a perineurium distended with fluid. A single large nerve fiber 

 enters one end of the corpuscle and loses its myelin as it traverses the 

 lamellae. It extends through the semifluid core without obvious branches, 

 sometimes being flattened and band-like; it may fork at its further end 

 or form a coil of branches, and it has been observed to pass out and enter 

 another such corpuscle. Usually the corpuscles are sectioned obliquely 

 or transversely so that the concentric layers completely encircle the inner 

 core. 



Special methods have shown that the axial fiber may possess many 

 short lateral branches ending in knobs, and that one or more delicate 

 fibers may enter (or leave) the corpuscles in addition to the large one just 



Sensory nerve fibers. 

 Muscle fibers. 



Motor plate. 



Medullated nerve fibers. 

 Nerve fiber bundle. 



FIG. 157. MOTOR NERVE ENDINGS OF INTERCOSTAL MUSCLE FIBERS OF A RABBIT X 150. 



described; they form a net surrounding the axial fiber. A small artery 

 may pass into the corpuscle beside the nerve and supply the lamellae 

 with capillaries. Lamellar corpuscles are abundant in the subcutaneous 

 tissue of the hand and foot and occur in other parts of the skin, in the 

 nipple, and in the territory of the pudendal nerve; they are found near 

 the joints (particularly on the flexor side) and in the periosteum and peri- 

 mysium, in the connective tissue around large blood vessels and nerves, 

 and in the tendon sheaths; also in the serous membranes, particularly 

 in the mesenteries. According to Schumacher (Arch. f. mikr. Anat, 

 1911, vol. 77, pp. 157-191) the lamellar corpuscles become inflated when 

 the blood-pressure is increased, and "their structure and distribution, 

 together with the results of experiments, indicate that they are regulators 

 of the blood pressure." 



