Stromatoporolds and of Eozoon. 447 



tliose Eozoic and Palaeozoic Foraminifera were related to 

 tiiose of later ages. I hope in this brief preliminary com- 

 munication to show that a great advance has been made and 

 tiiat it is now possible clearly to recognize the plan of growth 

 and organization, and to indicate with some degree of proba- 

 bility the relationships existing between the ancient and 

 modern forms. 



In my last paper I had stated that the stellate patterns or 

 " astrorhizai " so often found on the surface of Stromato- 

 poroids could be accounted for by assuming that the outer 

 ends of several mural tubuli became united to form one large 

 orifice ; but I soon discovered the incorrectness of this view, 

 and at the same time suspected that the clue to the Stromato- 

 poroid problem was to be sought in the astrorhizae. 



While examining a broken fragment of Slromatopora I 

 carefully mapped out the exposed chambers as seen on a 

 tangential surface, and here and there made out several series 

 showing a concentric arrangement in relation to an astrorhiza. 

 Then it occurred to me that we had hitherto viewed Stromato- 

 poroids from a wrong aspect, viz. the vertical, whereas the 

 liorizontal or tangential aspect was the one which revealed 

 the mode of growth. The coiled series of alternating 

 chambers reminded me of Orhitolites, and soon it became 

 clear that astrorhizse were the- central and circumambient 

 chambers of a spiral system, and that the multiple systems 

 must have arisen by budding in some way. 



Prof. F. Eoemer* had spoken of certain Stromatoporas 

 from the Eifel with surface tubercles each having a hole at 

 its summit leading down to the orifice of a small specimen of 

 Spirorbis omphalodes. He surmised that the little creature 

 prevented the growth of the Stroniafopora layers, and so kept 

 up its communication with the outside world. The Spirorbis 

 was probably nothing but the central and circumambient 

 chamber of a Foraminiferan. This particular 6p,(f)a\o<; might 

 in a sense be compared with that of the temple of Apollo at 

 Delphi in being the centre of the ytroniatoporoid and the hub 

 of its universe. 



Curiously enough, G. Lindstrom makes a similar observa- 

 tion about a S/Arorbi,<i saving itself from death by keeping 

 open a passage of communication f. 



The whole plan of Stromatoporoid organization now became 

 delightfully obvious. A polished slab of any Stromatopora 

 revealed clearly the numerous systems of spirally arranged 



* Geol. jNJag. 1880, vol. vii. p. 345. 



t K. Svenska Vetensk.-Akad. Handl. 1870, vol. ix. no. 0, p. 8. 



