The histologic findings in the papular, vesicular, nodular and Norwegian variants of scabies [Sarcoptes scabiei] have in common a superficial and deep perivascular mixed inflammatory cell infiltrate of lymphocytes, histiocytes and numerous eosinophils. A spongiotic vesicle occurs in the papulovesicular type, a dense cellular infiltrate in the nodular type and a hyperkeratotic psoriasiform dermatitis in the Norwegian type. Eggs, larvae and adult mites are abundant in the cornified layer of Norwegian scabies, are practically never found in biopsy specimens from lesions of nodular scabies and are discovered only episodically in papulovesicular lesions.