Figure 4

Chitin is present in serosal cuticle. (A-L) Calcofluor was used to reveal chitin in the serosal cuticle: labeling of embryos (A-H) or isolated SC (I-L). Panels exhibit fluorescence (fluo) alone or together with DIC (fluo + DIC), as indicated. Negative controls (-Calcofluor) confirm absence of auto-fluorescence in all samples. (A-D) Posterior half of clarified 9-HAE; (E-H) 15-HAE embryos; (I-L) Isolated SC from embryos at the end of development, broken at the line of dehiscence, without the egg shell cap. J is a lateral view. (M-P) WGA staining of isolated SC. Panels exhibit dark field or fluorescence (fluo), as indicated. (M, N) Non labeled control; (O, P) Labeled SC. See item 7 of Methods. Black arrow: serosal cuticle. White arrow: clarified endochorion. Bar = 100 μm.