whereas the goblet cells also stain weakly positive for protein (Millon reaction) (Fukuda, 1988; Muntz and Wentworth, 1995).
In an earlier review article (von Byern et al., 2010a) we provided some basic information on the epithelial glands and secretory composition of the Nautilus adhesive system. Apart from the two cell types already described by Fukuda (1988) we found an additional cell type (named cell type 1)