LARVAL DEVELOPMENT OF BALANUS EBURNEUS IN THE LABORATORY

Abstract

A technique has been devised for rearing segregated barnacle nauplii, under controlled laboratory conditions, which permits daily observations on the frequency of molting, the number of stages, and the specific characteristics of each stage. From a study of 121 segregated Balanus eburneus, plus hundreds in mass culture, reared on Chlamydomonas sp. and Arbacia larvae at 26° C. the following conclusions may be drawn:1. Ecdyses provide a definitive method for staging nauplii. The larval phase of B. eburneus consists of six naupliar stages and one cyprid stage. Secondary criteria, such as body size, spine structure, and appendage setation, are given for the larval stages.2. The duration of the six naupliar stages is as follows: first stage, 15 minutes to 4 hours; second stage, one to two days with an average of one day; third stage, one to four days with an average of 1.5 days; fourth stage, one to four days with an average of two days; fifth stage, one to five days with an average of 2.6 days; and the sixth ...