THE DEVELOPMENT OF CARETTA-CARETTA, AT 25-34-DEGREES-C, IN ARTIFICIAL NESTS

Scanning electron microscopy has been used to enhance the description of a single species, Caretta caretta (the loggerhead turtle), staged according to Miller's system for the development of marine turtles. Incubation over a temperature range of 25-degrees-34-degrees-C confirms previous observations that, under artificial conditions and at a constant incubation temperature, normal development is confined to a limited temperature range. Premature pipping is a feature of incubation at the lower end of this range; abnormal development, generated during the first third of the incubation period, occurs just above the normal range. Details of the external morphology of embryos from Miller stage 14 through to 25 are given together with an account of the developmental abnormalities produced at a high temperature of incubation. The data obtained confirm that Miller's scheme is generally applicable to C. caretta, provided that due regard is paid to the incubation temperature.