You have a mixture of fossil fragments of very different taxa, but most of them look like fragments of bryozoan colonies (the "perforated" ones).

Is it belongs to coralline facies, major fragments belongs to bryozoans  and few of them look like  gastropods. Krishnan Ayyasami is the renowned person who did lots of work in the ariyalur cretaceous. If you wish, you can contact on this link.  https://www.researchgate.net/profile/Krishnan_Ayyasami

Hi! There are overall bryozoan colonies and some fragments of gastropods 

and bivalves.

Best regards, Riccardo

Polypora sp. ??

The skeletal parts represent Bryozoans and some fragments of Gastropods

... a world of coralline facies in a beach sediment, ... maybe not cretaceous, ciao luca.

 probably  the fossils are bryozoan debries

Shell hash deposit, comprises of Bryozoa and fragmented parts of gastropods

Thank you all professors, scientists and researchers

Where from you took the picture (means stratigraphy, location etc.)?