Taxonomic history:
   1753: Linnaeus described this species as Lycopodium phlegmaria on p. 1101 of Species Plantarum.
    today: The current name for this species is Huperzia phlegmaria (L.) Rothm.

original Latin diagnosis
Lycopodium foliis verticillato-quaternis, spicis terminalibus dichotomis.

English translation
Lycopodium with leaves in whorls of four; [and] with spikes terminal [and] dichotomous.

English translation with commentary

Lycopodium	Lycopodium
with leaves	foliis - ablative plural of 2nd declension neuter noun folium, -i
in whorls of four;	verticillato-quaternis = verticillato- (combining form of group A adjective verticillatus, -a, -um) + quaternis (ablative plural neuter of group A adjective quaternus, -a, -um)>; modifies foliis
[and]	[added for smoother reading]
with spikes	spicis - ablative plural of first declension feminine noun spica, -ae
terminal	terminalibus - ablative plural feminine of group B adjective terminalis, -is, -e; modifies spicis
[and]	[added for smoother reading]
dichotomous.	dichotomis - ablative plural feminine of group A adjective dichotomus, -a, -um; modifies spicis