CALCAREOUS ALGAE OF THE MIDDLE EAST 63 



abundant microfossil in the Lias of the circum-Mediterranean area, namely Spain, 

 Italy, Greece, Morocco and Algeria. Its total range appears to be from within the 

 upper part of the Lower Lias, through the Middle Lias, and into the lower part of the 

 Upper Lias ; there are records from top Triassic which need confirmation (Sartoni & 

 Crescenti 1962). The usual associated microfossil is the foraminifer Orbitopsella 

 praecursor (Giimbel) . In the Middle East P. mediterraneus is known to me only from 

 Oman, where it is locally abundant in one bed of the Dolomitic Limestone of the 

 Lower Musandam, associated with algal nodules, and probably of Middle Liassic age 

 (see Hudson & Chatton 1959 : 78). Orbitopsella is known from S.W. Persia, but I 

 have not seen Palaeodasycladus associated in this limestone, though it is likely to 

 occur there. A. Gollestaneh has, however, recently discovered this dasyclad in the 

 lower to middle Lias of Khaneh Kat, interior Fars province. It is interesting that in 

 Oman, Orbitopsella occurred more or less throughout the Liassic rocks, whilst 

 Palaeodasycladus was restricted to one bed : in southern Italy, however, the alga has 

 a much greater vertical range than the foraminifer (Sartoni & Crescenti, 1962 ; de 

 Castro 1962). 



P. cf. mediterraneus from the subsurface Jurassic of Haifa, Israel, is Middle 

 Jurassic in age (Maync, 1966 ; Derin & Reiss 1966). 



In general, the Oman material confirms the accuracy of Pia's original reconstruc- 

 tion of Palaeodasycladus (Pia 1920 : 121). Sizes reached are less than those of large 

 Italian specimens, for which 12 mm. length and 2-8 mm. maximum external diameter 

 are quoted (Sartoni & Crescenti i960 : 14). Although the dolomitised nature of the 

 Oman specimens is not ideal for elucidation of fine detail, there appear to be several 

 small differences. The ragged outline of the stem-cell cavity, clearly figured by Pia 

 and ascribed by him to incomplete inner calcification on alternate verticils, was only 

 seen on one incomplete example, where it may well be due to the dolomitisation of the 

 stem-cell filling. The branches, although constricted as figured by Pia, appeared less 

 swollen and slimmer than in his reconstruction, and although constriction of tertiaries 

 without branching does occur, it was much less marked than in his figures. Finally 

 Pia's reconstructed successive cross-sections [op. cit. : 121), show a reduction in the 

 number of branches per verticil, from base to apex, 18 to 12, so accommodating the 

 increased branch-complexity. In the Oman material this is much less obvious, if it 

 occurs at all, and although counts of branching are difficult on sections of this 

 crowded, highly-oblique, structure, about 20 branches have been counted at a large 

 verticil. This is apparently to be correlated with the thinner branches already noted. 

 It is suggested that Palaeodasycladus retains the number of branches per verticil 

 during growth, or even increases them slightly like many other dasyclads, and that 

 the reduction seen in Pia's admirable clear figures is a cartographic necessity rather 

 than an accurate depiction. 



The Oman material is referred here to P. mediterraneus, and there is no reason to 

 make it a new species or variety. It is not comparable with the distinctive P. 

 mediterraneus elongatulus (Praturlon 1966). 



The modern appearance of Palaeodasycladus is striking when compared with some 

 of Pia's other bizarre reconstructions from the Mesozoic. Probably the spores were 



