Nature of Chloragogen Granules

Abstract

IT has become generally accepted that the chloragogenous tissue of earthworms is excretory in function and that the granules consist chiefly of guanine. This view is to be found in both elementary and more advanced text-books and is based on the work of Willem and Minne¹. Theirs is not the only work, however, and during the first decades of this century a number of papers were published on this problem. The evidence supporting the excretory nature of the chloragogen is conflicting and that for the alternative theory of the elaboration and storage of food reserves is equally contradictory. Many new techniques have been developed since this early work and it seemed desirable to re-investigate the problem using modern methods. Moreover, past work was done on sections and on the whole gut, and no attempt was made to separate the granules.