210 Frances L. Parker 



Specimens, some of which are filled with glauconite. This suggests that little deposition 

 has taken place in this area for a long time, since at most stations the planktonic 

 specimens appear to be fresh and well-preserved, showing recent deposition. It is 

 possible that there is a strong current in this area which removes the specimens as they 

 are deposited, leaving the older, filled tests. 



The planktonic populations in the Mediterranean probably are derived in two ways : 

 from material brought in by the Atlantic current and from ancestral stock indigenous 

 to the area, a so-called " relict " fauna. A third possible source may be transport 

 through the Suez Canal, but too little is known about this at the present time to 

 evaluate its importance. A study of Table I and of the specimens themselves leads to 

 some interesting speculations on this point. Phleger (1947) believes that occasional 

 specimens of GloborotaJia scitula are introduced from the Atlantic, but that the species 

 is not found living here. The present findings point to the same source, but it is 

 probable that there is some survival as there is a scattered occurrence of the species 

 throughout the area. Globigerinoides conglobata and Globorotalia hirsuta, which occur 

 rarely at many stations, may have a similar origin. On the other hand Globigerina 

 digitata and Hastigerina pelagica, which are rare in modern Atlantic sediments, may 

 be species indigenous to the Mediterranean. The atypical form of Globigerina eggeri 

 found in the Aegean Sea is probably an indigenous form. 



A recent study of the coiling direction of Globorotalia truncatulinoides by Ericson, 

 WoLLiN and Wollin (1954), shows that the North Atlantic may be divided into 

 provinces in which there occur " races " showing a dominance of left or right coiling. 

 According to their interpretation the area immediately west of Gibraltar should 

 contain a population showing equi-directional coiling. Samples from Atlantis stations 

 4637, 4735 and 4736 were examined and this was found to be the case. East of 

 Gibraltar at station 4734 the ratio shifts to 79 % left coiling (based on 62 specimens) 

 and increases rapidly to the east until at station 4730, just east of 0° Long., a domin- 

 ance of 99 % left coiling is found. High ratios of 88 % or more are maintained eastward 

 to station 4711, just west of 20° E. Long., which shows 62% left coiling. Farther east 

 there are too few individuals to give significant results. Where possible, 400 specimens 

 were counted and such samples served to check neighbouring stations containing 

 fewer specimens. These results also suggest that at least part of the Mediterranean 

 populations are indigenous and not directly derived from the Atlantic. A study of 

 other species by statistical analysis of measurements or other characteristics and a 

 comparison with Atlantic specimens would give additional data on this point, 



REFERENCES 



Di Napoli-Alliata, E. (1952), Foraminiferi pelagici e facies in Italia. Atti VII Com. Naz. Met. e 



Petr., Taormina, 1952, 1-34. 

 Ericson, D. B., Wollin, G. and Wollin, J. (1954), Coiling direction oi Globorotalia truncatulinoides 



in deep-sea cores. Deep-sea Res., 2, 152-158. 

 Kruger, D. (1950), Variations quantitatives des protistes marins au voisinage du Port d'Alger 



durant hiver 1949-1950. Bull. Inst. Ocean., Monaco, 978, 1-20. 

 Muraour, p. (1954 a), Sur quelques sediments dragues au large du littoral compris entre ie Cap 



Djinet et rembouchure de j'Oued Sebaou. Recherches sur les Fonds Chalutables de la Region 



d'Alger. Com. Loc. Ocean. Etudes Cotes Algerie, 91-107. 

 Muraour, P. (1954 b), Etude d'une vase prelevee a 700 metres de profondeur, au large de la Baie 



de Castiglione. Recherches sur les Fonds Chalutables de la Region d'Alger. Com. Loc. Ocean. 



Etudes Cotes Algerie, 123-132. 

 Oren, O. H. (1952), Some hydrographic features observed off the coast of Israel. Bull. Inst. Ocean., 



Monaco, 1017, 1-9. 



