Taxonomic history:
   1753: Linnaeus described this species as Panicum crusgalli in Species Plantarum, 1st ed., p. 56.
   today: The current name for this species is Echinochloa crusgalli (L.) P. Beauv.

original Latin diagnosis
Panicum spicis alternis conjugatisque, spiculis subdivisis, glumis aristatis hispidis.

English translation
Panicum with spikes alternate and connected; with spikelets nearly divided; [and] with glumes awned [and] hispid.

English translation with commentary

Panicum	Panicum
with spikes	spicis - ablative plural of first declension feminine noun spica, -ae
alternate	alternis - ablative plural feminine of group A adjective alternus, -a, -um; modifies spicis
and connected;	conjugatisque = conjugatis (perfect passive participle, ablative plural feminine) + -que (and); modifies spicis
with spikelets	spiculis - ablative plural of first declension feminine noun spicula, -ae
nearly divided;	subdivisis - ablative plural feminine of perfect passive participle of third conjugation verb subdivdo, subdividere, subdivisi, subdivisum; modifies spiculis
[and]	[added for smoother reading]
with glumes	glumis - ablative plural of first declension feminine noun gluma, -ae
awned	aristatis - ablative plural feminine of group A adjective aristatus, -a, -um; modifies glumis
[and]	[added for smoother reading]
hispid.	hispidis - ablative plural feminine of group A adjective hispidus, -a, -um; modifies glumis