62 



CALCAREOUS ALGAE OF THE MIDDLE EAST 



with up to 20 branches, in which the primaries are inclined outwards and upwards at 

 45-50 ° from the horizontal, and the subsequent branchlets curve outwards at a 

 lessening angle. Each primary gives rise to four or more secondaries, and these in 

 turn to about the same number of tertiaries ; all branches and branchlets are sharply 

 constricted terminally, slightly swollen between to give a slim sausage-shaped out- 

 line, and the tertiaries may themselves be constricted, without branching, before the 

 final termination expansion. The branches from the lower verticils, at lesser 

 diameters, are simpler in structure than the much larger terminal ones : the 

 transition is gradual. 



Horizon. Lias of Southern Europe, North Africa and the Middle East. 



Material. Numerous random thin-sections from one level in the median 

 dolomitic limestone of Group a (Liassic) of the Lower Musandam Limestone ; 

 Wady Bih, Jebel Hagab, Peninsular Oman (Hudson & Chatton 1959). 



Remarks. Palaeodasycladus mediterraneus is a characteristic and locally- 



Fig. 5. Reconstruction (after Pia 1920) of Palaeodasycladus mediterraneus Pia. Vertical 

 section on left ; decalcified appearance on right. X12 approx. 



