. Hand-book of physiology . o certain parts of the brain and spinal cordthe peculiar greyish or reddish-grey aspect by which theseparts are characterized. They are large nucleated cells, filledwith a finely granular material, some of which is often darklike pigment: the nucleus, which is vesicular, contains anucleolus (fig. 42). Besides varying much in shape, partlyin consequence of mutual pressure, they present such othervarieties as make it probable either that there are two diffe-rent kinds, or that in the stages of their develoj)ment, theypass through very different forms. Some of them are
. Hand-book of physiology . o certain parts of the brain and spinal cordthe peculiar greyish or reddish-grey aspect by which theseparts are characterized. They are large nucleated cells, filledwith a finely granular material, some of which is often darklike pigment: the nucleus, which is vesicular, contains anucleolus (fig. 42). Besides varying much in shape, partlyin consequence of mutual pressure, they present such othervarieties as make it probable either that there are two diffe-rent kinds, or that in the stages of their develoj)ment, theypass through very different forms. Some of them are small,generally spherical or ovoid, and have a regular uninterruptedoutline (fig. 42). These simj^le nerve-corpuscles are mostnumeious in the sympathetic ganglia. Others, which arecalled caudate or stellate nerve-corpuscles (fig. 43), are larger, VAKIETIES OF NERVE — CORPUSCLES. 387 and have one, two, or more long processes issuing from them,which processes often divide and subdivide, and appear tubu- Fig. 42.* Fig. lar, and filled with the same kindof Q-ranular material as is contain-ed within the corpuscle. Of theseprocesses some appear to taper toa point, and terminate at a greateror less distance from the corpus-cle ; others may be traced until eachof them, gradually losing its gran-ular appearance, becomes contin-uous with, and acquires all the characters of, a perfect n-erve-fibre (fig. 44). It is probable that many nerve-fibres, when they enter anervous centre, terminate, or perhaps, more correctly, origi-nate in this mode of connection with nerve-corpuscles. Asthey enter, the fibres gradually become finer: some, possibly.
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