TY - JOUR N2 - Septal neck-siphuncular complex has been redescribed In Triassic (Carnian) Stolleyites tenuis (Stolley). Ammonites whose septal necks change orientation from retrochoanitic through intermediate to prochoanitic may be divided into two categories: dorsoprogressive and ventroprogressive. In the former category, the initial changes in the direction of septal necks orientation occur dorsally; in the latter, the ventral side exhibits more progressive changes. Among forms with siphuncular complex adjacent to the ventral wall, i.e., without a septum between the neck and ventral wall in the medial plane, the changes towards prochoanitic septal neck may begin in the ventrolateral part. The circumsiphonal invagination in those forms did not include the ventral part and their proper interpretation cannot rely on the medial plane only. Primary lamination and primary fibrous structure of the siphuncular tube had been described, as well as the microstructure of the distal tip of cuff and auxiliary deposit. L1 - http://www.czasopisma.pan.pl/Content/111014/PDF/1994-1-2_037-049.pdf L2 - http://www.czasopisma.pan.pl/Content/111014 PY - 1994 IS - No 1-2 EP - 49 KW - Arctic KW - Edgeƶya KW - Triassic KW - paleontology (Ammonoidea) A1 - Kulicki, Cyprian PB - Polish Academy of Sciences PB - Committee on Polar Research VL - vol. 15 DA - 1994 T1 - Septal neck-siphuncular complex in Stolleyites (Ammonoidea),Triassic, Svalbard SP - 37 UR - http://www.czasopisma.pan.pl/dlibra/publication/edition/111014 T2 - Polish Polar Research ER -