"Species" the plural form

[Andrew K. Rindsberg]

Sean R. Edwards asks about the plural of "virus". According to Cassell's
Latin Dictionary, "virus" means "slime, slimy liquid, poison" and the
plural is "viri". But the English plural, following Webster's, is
"viruses".

There is similar confusion over bacterium/bacteria, phenomenon/phenomena,
where people tend to use the plural form as a singular, as in, "This is an
interesting phenomena," which can be made plural as "These are interesting
phenomenas." Makes my skin crawl.

Andrew K. Rindsberg

Geological Survey of Alabama
Tuscaloosa, Alabama, USA