This is a picture of nits that are on one strand of hair. The nits hatch in 7-10 days. Adult lice live for about 30 days. Adult head lice are the the size of the period at the end of this sentence. The picture on the right shows adult head lice.
Head lice are tiny parasites that are smaller than a sesame seed.
They like warm, humid conditions, and are adapted to live only on the human head. They are not the same lice that are found on dogs, birds, or other animals. They feed on blood, and it is their biting that causes the itching that is a usual symptom of head lice infestation. Checking for Head Lice Lice do not jump or fly, but they do crawl quickly. They are repelled by light and will scurry to to hide behind a hair shaft.