Studies on the digestion of wool by insects. V. The goblet cells in the midgut of larvae of the clothes moth (tineola bissellielal (humm.) and other lepidoptera.

Goblet cells and columnar cells occur, together with regenerative cells, in the midgut epithelium of lepidopterous larvae. The columnar cells have an appearance typical of the simple epithelial cells that occur in the midgut of many insects. The goblet cells are highly differentiated and, although there are marked variations between species, such as in frequency of occurrence, in shape, in staining reactions, and so on, their basic structure is very similar. Bodian's 'ProtargoI' staining technique provides excellent differentiation of goblet cells. Each goblet cell has a basally situated nucleus and contains an internal cavity, which is bordered by a faintly striated lining. No opening permitting direct movement of material from the cavity into the lumen has been observed. Available evidence suggests that materials moving out of the cavity pass through a bounding membrane. Unlike columnar cells, goblet cells do not possess a striated border on their lumen surface.