120 



G. LINDSTRÖM, HELIOLITID^. 



Fis. 23. 



24. 



25. 



Part of the coenencliyma to show the in- 

 timate structure of tlie walls of tbe thecse. 



A portion of a calicle is visible on the left 



side. 34/i_ 

 Trausverse section of the coenenchyma of 



a specimen from the Devoniau of Graz, 



Austria, kiudly sent from Dr Peneckb. 



12/1. 



Longitudinal section of the same. '^/i. 



Fig. 26. Longitudinal section of coenenchyma from 

 the same specimen as in fig. 18, to show 

 how the tabuloe are on both sides covered 

 with crystalline growth, the tabulse looking 

 white between. 

 » 27, 1 — IV. A series of sections showing the coenen- 

 chymal gemraation. ^"/i- Bevelopment be- 

 ginning at section I. Distance between i 

 and IV the fraction af a millimeter. 



i 



Heliolites parvistella Ferd. Roemer p. 60. 



Fig. 28. Part of the surface of the original specimen 

 of Roemer, belonging to the Geological 

 Museum of the University of Breslau, 

 communicated by Prof. Frbch, found at | Fig. 30. 

 Sadewitz in Schlesien. ^^/i. I 



» 29. Longitudinal section of the same. *Vi- Ori- 

 ginal in tho Museum of Breslau. The 

 brackets in this and several of the following » 31. 



figures are intended to indicate the width 

 of the calicular tube, as it is difficult to 

 distinguish it from the coenenchyma. 



Transverse section of a specimen from Patta- 

 kumäggi, Isle of Oesel, Upp. Sil. 'Vi- 

 Part of a specimen in the Museum of 

 Reval. 



Longitudinal section of the same. '°/i. 



