CALCAREOUS ALGAE OF THE MIDDLE EAST 19 



radial tubes, slightly curved but approximately horizontal, about 20 in number, 

 which are interpreted as the calcareous coatings or casings of simple primary side- 

 branches. These are free for much of their length, but touch and become fused 

 centrally, to form a circular ring through which the stem-cell passed. Pores on the 

 inner surface of the ring mark the old communications of side-branches with stem- 

 cell. A succession of such verticils built up in life the peculiar plant shown in Pia's 

 reconstruction (fig. 2). 



Subsequently Carozzi (1948) figured numerous thin-sections determined as 

 Adinoporella podolica, from the Swiss Portlandian-Purbeckian. It is with these 

 sections that the Middle Eastern material has been correlated, no solid individuals 

 having been extracted. The commonest thin-section appearance is given by 

 tangential cuts through the finger-like projections or side-branches, which show as 

 chains of separate or touching circles. Less commonly vertical sections along the 

 main axis show the central stem-cell and paired opposite side-branches, and rarely, 

 transverse cuts show a whole disc or verticil. 



Although locally common in the European Portlandian, and recorded from as low 

 as Sequanian (Francois, Lehmann & Maync, 1958), this alga is characteristic in the 

 Middle East of the Lower Cretaceous and has never been seen there in the Jurassic. 

 In Italy (Sartoni & Crescenti 1962) it is recorded from both Tithonian and Valan- 

 ginian-Hauterivian. It appears to be slightly more common in the Middle East at a 

 Valanginian-Hauterivian level than in the Barremian-Aptian above (Elliott 1955b), 

 but forms a noticeable constituent of the Middle Eastern " debris-facies " (Elliott 

 1958a), an off-shore accumulation of fine calcareous algal fragments in fire-grained 

 sediments. 



The relationship of Adinoporella to Clypnna, and their positions within the family 

 Dasycladaceae, are discussed elsewhere (p. 99). 



Adinoporella podolica Alth 

 (PI. 1, figs. 2, 4, 7) 



1878 Gyroporella podolica : Alth : 83, pi. 6, f. 1-8. 



1882 A ctinoporella podolica Alth : 322. 



1920 A. podolica Alth ; Pia : 95, fig. 19, pi. 7, f. 1-7. 



1948 A. podolica Alth ; Carozzi : 353, f. 49. 



1955b A. podolica Alth ; Elliott : 126, pi. 1, f. 1. 



1958a A. podolica Alth ; Elliott : 255, pi. 45, f. 1. pi. 47, f. 5. 



i960 A. podolica Alth ; Elliott : 222, 223. 



Description. Verticils of from i-o to i-6 mm. or more total diameter, each con- 

 sisting of a central calcareous ring with inner diameter of about 21% of the total 

 diameter ; from this ring project 13 to 20 largely separate tubular elongate thin- 

 walled cylindrical rays, outwardly directed and all very gently curved upwards on 

 the same side of the horizontal plane. Near and at the ring the walls of the rays are 

 fused, to give a thickened calcareous structure, and the hollow interiors of the rays 

 communicate each by a single pore with the main central cavity. 



