External morphology of eri (Samia cynthia ricini Boisduval) egg during embryonic development

Abstract

This study was conducted to gain better understanding of the features of eri (Samia cynthia ricini Boisduval) egg during progressive embryonic development. The eri egg is oval, flat and broader at the anterior region. The follicular imprints are evenly distributed over the chorion. The creamy white egg colour changed to grayish bluish on the eighth day. The length and width of egg changed on the eighth day after oviposition. The egg mean length was positively related with its width (r=0.9938). Except for an increase on the third day, there was a gradual reduction in egg weight through progressive embryonic development.