The specimen shows three adult worms; these are usually grey in colour, but have been discoloured
during preservation. The adults range in length from 15 - 30cm, and from 0.3 to 0.5cm in diameter.
The eggs are deposited in the soil, where they undergo a period of incubation. The infection is
acquirted by ingestion of the fully embryonated ova. The larvae are hatched in small intestine, and
penetrate the wall, reaching the lungs by way of venules, or lymphatics. They pass into the alveoli
from the alveolar capillaries, and migrate up to the main bronchial tree and down the oesophagus
with swallowed saliva. In the small intestine, they grow into adults of male or female sex. The
most frequent complications are caused by the adult parasite producing intestinal obstructions.