Beautiful Algae
Diatoms (Bacillariophyceae) are water-dwelling microscopic photosynthetic organisms—algae—with elaborate glass shells. In other words, they are tiny plants (although some of them can move) that live in beautiful glass houses in water.
Glass Houses
These glass houses are of many sizes and shapes, with spines, pores and slits, but they are always made of two pieces (called valves). Diatoms are found anywhere where there is at least one drop of water. That means streams, oceans, sewage water, and also wet rocks, backyard pools, and a manatee's skin.
Although very small in size, they are essential for all living organisms. Diatoms living just in the oceans are responsible for producing about a quarter of the world’s production of oxygen, which all living things need to survive.
The Diatom Herbarium at the Academy of Natural Sciences of Drexel University is one of the two largest such collections in the world; the other is at the Natural History Museum, London.
The Academy’s collection includes 220,000 slides, of which 5,000 are types, and much of it is available in an online database.
The collection, dating back before the 1800s, is a primary source of taxonomic and ecological information.
Biddulphia arctic var. pentagona by Marina PotapovaAcademy of Natural Sciences of Drexel University
Navicula oamaruensis light microscope by Marina PotapovaAcademy of Natural Sciences of Drexel University
Staurosirella sp. by Eduardo MoralesAcademy of Natural Sciences of Drexel University
Detail of areolae on the surface of Epithemia sp. by Marina PotapovaAcademy of Natural Sciences of Drexel University
Amphora sp by Eduardo MoralesAcademy of Natural Sciences of Drexel University
Didymosphenia geminata by Eduardo MoralesAcademy of Natural Sciences of Drexel University
Opephora sp. by Eduardo MoralesAcademy of Natural Sciences of Drexel University
Cocconeis sp. by Eduardo MoralesAcademy of Natural Sciences of Drexel University
Planothidium sp. by Nina DesiantiAcademy of Natural Sciences of Drexel University
Biremis circumtexta by Eduardo MoralesAcademy of Natural Sciences of Drexel University