Another example of a species in which I have hunted from layered granules in the alveolar type II cells is hamster (though only a few animals have been studies). There are, as in cat and rabbit) frequent examples of RER which has a slightly dilated appearance, and also has obvious protein density within the lumen of the profiles, but lacks all but the very faintest appearance of layering, and also does not abide by the criterion for layered granules in that ribosomes stud all aspects of these RER profiles, and the rigid looking, ribosome free, part of the granules seen in ferret, guinea pig and dog, thus one has to assume either that surfactant protein A is sufficiently unique in the three species above where granules can organized into a regular substructure, or that something else altogether is responsible.  hamster, male, animal# 3, neg 7278, block 24733,