, 1m Kleinsten die wirkliche Wahrheit gibt graBen Gedanken erst
Klarheit" KARL THOMAS Each year sees the publication of hundreds of
reports of experimental work on the lymphatic tissue, yet morphological
studies of the cells involved can be counted on the fingers of one hand.
Furthermore, anyone who tries to identify these cells by morphological
criteria is accused of sophistry and hair- splitting, whereas it is
accounted scientifically correct and unbiased to speak of "lymphoid
cells", "blast cells" etc. Not so many years ago things were different:
there were too many names and too many classifi- cations and everyone
backed his particular fancy. People thought of cells in terms of rigid
classes, nothing then being known about the transformability of
mononuclear blood cells. Today we must look for the middle way: cells
should be named and defined according to morpho- logical criteria but
their transformation potential should be borne in mind. Once the cells
are analysed and subdivided, it will be simple enough to set up proper
classifications afterwards. This book arose out of the conviction that
there should be more criteria and more information available on the
morphology of human lymphoreticular cells; previously such information
had been restricted by the difficulty of the special hematological and
cytochemical staining methods.