The literature on coated vesicles has been dogged with nomenclature problems and Bowers (1964) lists a plethora of synonyms for the organelle. Since coated vesicles were first described, terms such as complex vesicles, fuzzy vesicles, spiny vesicles, bristle-coated vesicles, dense-rimmed vesicles, alveolate vesicles and acanthosomes have all been employed. Because the majority of the data contained in this volume refers to the one organelle we have used the single term ‘coated vesicle’ throughout. We propose that for this organelle the use of all the other terms be dropped.

Against such a background it was not surprising to observe recently the beginnings of a rift developing over choice of a name for the major protein composing the polygonal structure on these vesicles' outer (cytoplasmic) surface (Matus, 1976; Pearse & Bretscher, 1976). The name proferred by Matus for this protein is dependent on Gray's (1972) interpretation of the vesicle coat as a fixation artifact. Gray had observed that the coated vesicles in his preparations of sectioned material for transmission electron microscopy were surrounded by an electron-lucent area. He concluded that material which had occupied this area in vivo was contracted during preparation for electron microscopy onto the surface of smooth vesicles giving rise to the polygonally patterned surface structure. Biochemical evidence and fine-structural information based on improved fixation methods make the artifact hypothesis hardly tenable.

Pearse's (1975) work which showed that the polygonal structure was composed for the most part of a single protein (mol. wt 180,000), has since been repeated and confirmed by several independent groups working on coated vesicles isolated from several different tissues.