Kachchh is a pericratonic basin in which Early Miocene sedimentation took place in a shallow marine environment. During the course of study of ostracods from these beds a detailed sampling carried out from a hill section (N 23°24',E 68°49') exposed about eight kilometres from Rampar village, towards Goyela-Matanomadh road. The sediment logical data and ostracod assemblage together reveals the fluctuation in relative sea-level. The change in ostracod assemblage in middle part indicating deepening i.e. middle shelf environment. This is followed by progressive shallowing of the basin marked by deposition of marl. The top part composed of limestone with full of mega fauna indicates again deeper water condition prevail in the area. The paleoecology of the genera viz. Actinocythereis, Neomonoceratina, Alocopocythere, Cytherelloidea, Pontocypris, Propontocypris, Pseudocythere, Semicytherura, Xestoleberis, Cytheropteron, Miocyprideis, Pokornyella and Occultocythereis is discussed in the paper.The overall evidence suggests that majority of the genera thrive well in near-shore to shallow marine environment and hence it is inferred that the beds of Early Miocene might have been deposited in near-shore to shallow marine conditions.

Neoichnological observations help refine paleoichnological records. The present study reports extensive observations on the distribution, morphology, occurrence and association of burrows and fecal pellets of the polychaete Nereis diversicolor in the Kundalika Estuary on the west coast of India. Our holistic study of these modern-day traces suggests it to be a complex trace arising from domichnial, fodinichnial and possibly pascichnial behavior of polychaetes. The study for the first time reports extensive fecal pellet production, distribution and their preservation as thick stacks in modern estuarine environment. These observations testify the fossilization potential of pellets and provide an explanation to their origin in the geological record. Their occurrence as strings associated with mounds not only suggests pascichnial behaviour of polychaetes but also allows the assignment of post-Paleozoic Tomaculum to the activity of polychaete worms. The production of fecal pellets in such large quantities plays a major role in increasing the average grain size of the substrate of these estuarine tidal flats, thereby improving aeration within the substrate.

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An interesting bivalve fossil obtained from the Claystone Member of the Chhasra Formation (Burdigalian), Kachchh District, India was found conspecific with Anadara gourae Dey (Arcidae, Anadarinae) from the Quilon Beds (Burdigalian), Kerala. However, this form is feebly inequivalve and has dissimilar ornamentation on the two valves, a trapezoidal form and its maximum height is at the posterior. Also, there is a small but distinct median sulcus on the exterior of the umbonal region. These characteristics do not agree with definition of the genus Anadara. Hence it is described here under a new genus, Indarca. Subgenus Cunearca Dall of genus Scapharca Gray (Arcidae, Anadarinae), also shows dissimilar ornamentation on the two valves, but differs from Indarca in having an inflated form, left valve slightly larger and absence of a sulcus on the umbonal region. Indarca resembles Bentharca Verrill and Bush (Arcidae, Anadarinae) in certain respects, but differs from it in not having a markedly reduced anterior. Occurrence of Indarca gourae strengthens the faunal affinity between the Chhasra Formation of Kachchh and the Quilon Beds of Kerala.