The fecundity (ratio egg-masses per snail, eggs per snail and eggs per egg-mass) and the fertility (hatchability and viability of eggs) of Biomphalaria glabrata and Biomphalaria tenagophila were compared during one year, in the laboratory. The average of eggs per egg-mass was significantly higher in B. glabrata (19.9) than in B. tenagophila (16.2) and both species showed highest fecundity during April. The influence of temperature was very small. The fecundity defined as egg-mass per snail per day was greater in […]