The species problem in Millepora

CONTENTS I. Introduction............. 3 II. Historical notes, including the successive views concerning the specific value of the growth forms.......... 6 III. The species of the genus Millepora........ 18 IV. Synonymy and geographical distribution....... 23 V. Discussion of the various characters for specific distinction .................................................... 44 VI. Notes on specimens of Millepora from the islands Edam and Noordwachter in the Java Sea........... 71 VII. Notes on specimens of Millepora in the Paris Museum ............................................................... 79 VIII. Notes on specimens of Millepora in the Leiden Museum ............................................................. 86 IX. Notes on specimens of Millepora in the Amsterdam Museum .................................................. 100 Literature............... 108 I. INTRODUCTION As a result of his studies on the growth forms of Millepora Hickson (1898 a, b, 1899) came to the conclusion that these various forms entirely are caused by different environmental factors, and that they are nothing else but manifestations of the extreme variability of the one species Millepora alcicornis L. Previously Hickson (1889) had seen more or less extreme growth forms on the reefs of North Celebes, and at that time he distinguished a more or less delicately branched growth form named by him Millepora alcicornis from a plate-like growth form named by him Millepora plicata. Now these growth forms are so strongly different that it seems a matter of fact that they are specifically distinct. Later, however, Hickson made an extensive study of material from expeditions and of