HISTORICAL BACKGROUND 459 



have evolved on land and thereafter migrated from the land to 

 the ocean. On the other hand, those who would derive the 

 Ascomvcetes from Florideae regard the fungi as polvphyletic. 

 They emphasize as a basis of relationship similarities between sex- 

 ual reproductive structures rather than the phenomenon of mo- 

 tility. Regardless of whether fungi are mono- or polvphyletic, 

 there do not seem to be adequate explanations to account for the 

 paucity of Phycomycetes and Ascomycetes within the oceans. 

 There should be an abundant population of marine fungi, primar- 

 ily because the ocean constitutes a relatively stable environment 

 which should be favorable for the continuous maintenance cf spe- 

 cies, without major adaptative modification, even of those whose 

 origin dates back into remote ^eolomc time. This environmental 

 stability may in itself be used to account for the lack of evolutional 

 development of new or different species. If numerous kinds of 

 marine fungi exist, the fact is not revealed by publications. In- 

 stead the literature on marine fungi conveys the definite impres- 

 sion that the oceans do not constitute the natural habitat of di- 

 verse fungi, nor are they at any place densely populated by any 

 given species. 



HISTORICAL BACKGROUND 



Evidently many of the early students of marine animals and 

 plants failed to recognize the presence of fungi among their col- 

 lections or else interpreted the fungi as structures possessed by the 

 animals or plants themselves. Nevertheless occasional observers 

 noted hyaline objects which were interpreted to be fungoid. In 

 1858 Wedl [Bornet and Flahault (1889)] observed that corals 

 from the littoral zone down to a depth of 1095 fathoms are fre- 

 quently invaded by filaments that lack septations and are termi- 

 nated by clavate cells resembling sporangia of the Saprolegniaceae. 

 Kolliker (1859-1860) made similar observations in his examination 

 of animals possessing calcareous shells. Stirrup (1872) observed 

 fungoid growths within the shells of molluscs, and Duncan (1876- 

 1877) identified as Achlya penetrans and Saprolegnia ferax two 

 water molds within the canals of Caryophyllia smithii, one of the 

 Aladreporia. Since these two species have not been found subse- 

 quently in salt water, their identification must be questioned. The 

 solvent action of carbon dioxide produced by the hyphal tips 

 made possible the penetration of the shells. Bornet and Flahault 



