PART IV 



REPORT ON A PROBABLE CALCAREOUS 



ALGA 



FROM THE CAMBRIAN LIMESTONE BRECCIA FOUND IN 



ANTARCTICA AT 85° S. 



(With Plate) 



BY 

 FREDERICK CHAPMAN, A.L.S., F.R.M.S. 



Palaeontologist to the National Museum, Melbourne 



INTRODUCTORY 



Several distinct types of fossil remains in Cambrian limestone from various parts 

 of the world have been referred, and probably rightly so, to the calcareous algae. 

 Notably amongst these are Confervites primordialis of Bornemann* (from Sardinia), 

 also recorded by Von Tollf (from Siberia) ; Epiphyton flabellatum, Bornemannt (from 

 Sardinia) ; and Siphonema [ = Girvanella] incrustans § and (?) arenaceum, Bornemann || 

 (from Sardinia). 



The genus Confervites above mentioned has generally been made a dumping-ground 

 for all organisms resembling modern seaweeds having a simple or branching thread- 

 like thallus. It seems tolerably certain that many of these simple seaweed-like 

 forms, to whatever botanical group they may belong, existed in prodigious abundance 

 in the earliest known rocks ; the evidence being strengthened by the fact that a large 

 number of these forms cannot be referred to trails, stains, or cracks in the sediments, 

 nor do they come within the definition of any group of animal organisms. Regarding 

 Confervites, Seward ]} remarks : " Numerous fossils have been referred to this genus 

 by different authors, but they are for the most part valueless and need not be further 

 considered." That author subsequently says (p. 178) : " It is possible that this 

 [Confervites Chantransioides of Bornemann] is a fragment of a Cambrian alga, but the 

 figures and description do not afford by any means convincing evidence." 



The present specimens form a considerable proportion of the limestone. They 



* " Die Vcrsteinerungen des cambrischen Schichtensystems der Insel Sardinien," Kais. Leop.- 

 Carol Deutsche Akad. Naturforscher, vol. li, 1887, p. 16, pi. ii, figs. 5, 6. 



f " Beitrage zur Kenntniss des sibirischen Cambrium, Pt. I," Mem. Acad. Imp. Sci. St. Petersb., 

 Ser. VIII, vol. viii, No. 10, 1899, p. 47, pi. viii, figs, lc, d, text fig. 9. 



J Bornemann, loc. supra cit., p. 16, pi. i, figs. 9, 10. 



§ Idem, loc. cit, p. 18, pi. ii, figs. 1, 2. See also Chapman, Rep. Aust. Assoc. Adv. Sci. Adelaide 

 Meeting, 1907, p. 7 (sep. copy), foot-note j, where it is stated that Bornemann's species is synony- 

 mous with Girvanella problematica, Nich. and Eth. fil. 



|| Idem, loc. cit., p. 19, pi. ii, fig. 3. 



f Fossil Plants, vol. i, Cambridge, 1898, p. 177. 



ii 81 M 



