First International Symposium on Dinosaur eggs and Babies, 24-26 September 1999. Isona i Conda Dellà (Spain), 7-8. FIRST RECORD OF ELONGATOOLITHIDAE EGGSHELL FRAGMENTS (DINOSAURIA) FROM CUESTA CORRALES 2 (LOWER BARREMIAN, TERUEL, SPAIN) Amo , O., Canudo , J. I. & Cuenca-Bescós, G. Grupo Aragosaurus. Área y Museo de Paleontología, Universidad de Zaragoza. C/ Pedro Cerbuna s/n, 50.009 Zaragoza. Spain. jicanudo@unizar.es http://www.aragosaurus.com/ The site of Cuesta Corrales 2 is a new site situated at the top of the Castellar Formation in Galve (Teruel). The fossiliferous beds at the top of Castellar Formation are a rich fossil assemblage of mainly isolated bones and teeth, probably accumulated in an ancient lacustrine - palustrine environment of earliest Barremian in age. The rich vertebrate includes Pycnodontiformes, Ammiformes, Hybodontiformes, Amphibia, Crocodylia, Ornithopoda, Sauropoda, Theropoda, Mammalia, Quelonia and Sauria. Previous works about dinosaur eggshell fragments in this area are those of Kohring (1990), who studied the material from Colladico Blanco site, and Amo et al . (1999), who described a association of vertebrate eggshell fragments from Camino Canales site. Both localities are situated at the top of the Castellar Formation, very close to Cuesta Corrales 2. The Cuesta Corrales 2 site contains only dinosaur eggshell fragments. 414 fragments were collected from the surface. The fragments range from 0.25 to 1 cm 2 in size. Forty four fragments were thin sectioned and twenty five were analysed under scanning electron microscopy. The thickness of the eggshell fragments varies from 0.40 to 1 mm excluding ornamentation and 0.55 to 1.45 mm including ornamentation. Thirty six fragments show dispersituberculate and coalescituberculate ornamentation with nodes of 0.3-0.7 mm in diameter. The rest of fragments show an outer surface with linearituberculate ornamentation. The pore system is of the angusticanaliculate type and it has pore canals ranging from 0.073 to 0.078 mm in diameter. The continuous layer to mammillary layer ratio (CL:ML) is of 2:1- 3:1 and the boundary of them is not abrupt but there is a change in structure. Horizontal accretion lines following the contour of the outer surface can be seen in the upper part of the shell. Near the pore canals the accretion lines are curved inward . The mammillae have diameters ranging from 0.13 to 0.27 mm. The continuous layer shows a columnar extinction pattern between nodes and wedge-like extinction under nodes and ridges under polarizing light.