Transmission electron micrograph showing the aggregation of rough endplasmic reticulum known as a Nissl bodiy within nerve cells of the superior cervical ganglion. Note that this very early (1953) micrograph is primarily of historical interest since it pre-dates glutaraldehye fixation which was introduced in the early 60's and is considered essential for adequate nerve tissue preservation. Examples of nerve tissue micrographs prepared in 1965 are CIL:37218, CIL:37219 and CIL:37220. Image made available by James D. Jamieson and the Department of Cell Biology, Yale University School of Medicine.