Growth curves and culture temperature. (a) Growth curves of five individuals and culture temperature drawn from Dataset Item 1 (Table). Arrows with specimen numbers denote when the specimen grows longer than the size at the beginning of observation. Growth lines are approximated by fourth-ordered regression curves. All specimens show growth arrest during metamorphosis. (b) Growth curve obtained by a cross-sectional sampling grouped according to developmental stages drawn from Dataset Item 2 (Table). All specimens again display growth arrest during metamorphosis. In the sampling at the postmetamorphic stage, well-grown animals were selected to avoid mixture with younger stages, which causes size difference at the postmetamorphic stages between the isolated culture (a) and pooled culture (b). Each measurement shows the mean ± SD. Premeta: premetamorphic stage; M1: thickening of secondary gill series; M2: bisection of secondary gill pores; M3: pairing of gill slits.