This is Nummulites vascus from Oligocene Abraq Formation in Cyrenaica- NE Libya. Is it a diagenetic in origin? Your suggestions are highly appreciated.
I guess the sphaerical cyst like objects are made of the similar calcareous material as the rest of the test. I would think it is diagenetic, as the organic matter of the nummulites decomposes, the PH can shift. Along these changing PH fronts carbonate might participate. I have very high uncertainty in what I am saying, as I have never seen anything like this in forams.
According to a colleague they are embryos of a new generation. In asexual or sexual reproductions in most forams, the newly divided individuals may be retained within the test of the adult until they secrete the initial chambers of their test then move out on their own. They use this time to grow and then the test either dissolves or is broken enzymatically by the babies.
I looked into the matter. I correct myself. My instinct to call it diagenetic was not right. It is more likely to be an embryo/proloculus. I found a reference, I attach it.
http://paleopolis.rediris.es/cg/CG2006_M02/
The attached part of the book is very helpful and many thanks to all of you, I can see they are a brood chambers by considering the comparative anatomy concept. Great job katalin to attach the illustration of the living Sorites orbiculus of the Gulf of Aqaba.
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