ECOLOGY AND TAXONOMY OF Halimeda 29 



Rijksherbarium of Leiden, the herbaria where most, if not all, of the 

 f. ovata material is deposited. 



The f. ovata specimens are relatively few, occasionally poorly 

 developed, and sometimes too scant to be adequately examined. 

 However, most of those on which it has been feasible to work are 

 micronesica, a species described in 1941 which will be discussed later 

 on p. 32, and which is of especial interest because of the pattern of 

 its nodal medullary filaments. A few are opuntia or simulans, the latter 

 a taxon in which the pores of the fused nodal filaments are sometimes 

 small and not readily noticeable (Hillis, 1959). It, therefore, presents 

 some of the gradations Barton indicated for this character in the above 

 quotation. These identifications of the anomalous f. ovata material have 

 clarified and to a certain extent strengthened the major portions of 

 Barton's work. 



In retrospect. Barton's taxonomy was conservative, which was 

 an approach much needed at the time. Its strengths lay in the discovery 

 of essentially one microscopic characteristic of major taxonomic 

 significance, in the fairly rigid application of it in identification, in the 

 emphasis on examination of type specimens, and in the inclusion of 

 material from other than the Siboga collection, which, although 

 severely limited, did extend the work to all the tropical oceans. After 

 the monograph was published. Barton continued identifying algae, 

 published one paper on reproductive structures in Halimeda (Gepp, 

 1904), and more on Siboga algae in the important joint publication, 

 with her husband, about the Codiaceae (Gepp and Gepp, 1911). The 

 work after 1911 was not extensive, however; there appeared to be little 

 further study of Halimeda, and one suspects that marriage in 1904 to 

 Anthony Gepp, Curator of Botany at the British Museum (Natural 

 History), and the contemporary attitude towards women and careers 

 had their impact. For a brief time, however, the genus Halimeda was 

 tidy. 



E. Howe, Borgesen, Taylor and Hillis: the modern taxonomy 



No taxonomic scheme of living organisms is fixed, however, and in 

 a very short time after the publication of Barton's monograph many 

 new collections became available to test the workability and validity 

 of her system. Initially specimens came mostly from the Caribbean, a 

 tropical region scantily represented in Barton's work, and for the first 

 time the material was studied by workers who had some responsibility 

 for collecting it. They were Marshall A. Howe of the New York Botanical 

 Garden and Frederick Borgesen of the Botanical Museum, Copenhagen, 



