In "Physics of Nearby Galaxies: Nature or Nurture?", 1992 T. X. Thuan, C. Balkowski, and J. T. Thanh Van, eds., Editions Frontieres, Gif-Sur-Yvette, p. 3

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ABSTRACT. Much of what is known about galaxies began with a simple classification of their forms as seen on direct blue-light plates. This classification continues to be useful at a time when galaxies have never been better understood. The reason for this is that morphology contains information on the dynamics and evolution of galaxies in spite of the fact that the features dominating the appearance may include only a small fraction of the total mass. In this article I briefly review the important classification systems in use today and highlight classification as an art having significant discriminating ability and at the same time serious limitations. I also summarize recent developments in this field from a morphologist's point of view.

Table of Contents

• INTRODUCTION
• REVIEW OF CLASSIFICATION SYSTEMS
• CLASSIFICATION AS AN ART
• TYPE CORRELATIONS
• RECENT DEVELOPMENTS IN CLASSIFICATION AND MORPHOLOGY
• CONCLUSIONS
• REFERENCES