ABSTRACT
The torpedoes exhibit yolk-sac viviparity (Ranzi 1932, 1934). The Pristiformes also exhibit yolk-sac viviparity (Thorson et al. 1983; Campagna 1990) and perhaps limited histotrophy. Observations by Setna and Sarangdhar (1949) of a "milky secretion" in the uterus of Pristis cuspidatus should not be misconstrued to mean that Pristis is histotrophic in the same way as the Myliobatiformes, which produce a histotroph rich in lipids. However, limited histotrophy, which involves production of mucoproteins in the uterus, is widespread among viviparous elasmobranchs (Chapter 13 of this volume) and may occur in the Pristiformes.
