Microscopy

A

A: Head Lice: Nit
Nits are head lice eggs.  They are hard to see and are often confused for dandruff or hair spray droplets.  Nits are laid by the adult female and are cemented at the base of the hair shaft nearest the scalp.  They are 0.8 mm by 0.3 mm, oval and usually yellow to white.  Nits take about 1 week to hatch (range 6 to 9 days).  Viable eggs are usually located within 6 mm of the scalp.

B

B: Head Lice: Adult female louse
The adult louse is about the size of a sesame seed, has 6 legs (each with claws), and is tan to grayish-white.  In persons with dark hair, the adult louse will appear darker.  Females lay up to 8 nits per day.  Females lay up to 8 nits per day.  Females are usually larger than males.