MagazinesNewspapersBuy Gift CardRedeem Gift Card
GB flagUnited Kingdom

Europe

Austria Belgium Bulgaria Croatia Czech Republic Denmark Estonia Finland France Germany Greece Guernsey Hungary Ireland Isle of Man Italy Jersey Latvia Lithuania Luxembourg Malta Netherlands Norway Poland Portugal Romania Slovakia Slovenia Spain Sweden Switzerland Ukraine United Kingdom

Asia

China Cyprus Hong Kong Indonesia Japan Philippines Saudi Arabia Singapore Thailand

Oceania

Australia New Zealand

Americas

Canada United States

Africa

South Africa
Magazines How It Works Magazine 17 March 2022Head of a hydroid

Head of a hydroid

1 min read
© Getty

Hydroids are invertebrates that either live alone or form c

This article is from...