Prions (PrP) are shed from sheep and goats in birth fluids, feces and other excrement. Substances such as urine, excrement, liquid manure, and sullage were used for this purpose. Streets were of dirt or occasionally cobblestone and strewn with garbage and human excrement. Guano (via Spanish from ) is the accumulated excrement of seabirds and bats. Guano (bird excrement) is harvested for use as a fertiliser. They also occasionally covered their work in urine and excrement. Dominant bulls mark their territory with excrement and urine. He found anthrax bacteria in earthworms' excrement, showing that he was correct. He, his wife, and his son were also forced into a heap of excrement. Clodius' gangs dogged him, hurling abuse, stones and even excrement. They suffered chronic dysentery and were made to lie in their excrement until morning. He describes his punishment in the afterlife as boiling in excrement. Then tongs were used to prise his mouth open after he refused to swallow excrement. It was reportedly packed with human excrement. The anemone also picks up nutrients from the anemonefish's excrement.