The third name of the trinomial nomenclature is of

$A$ group of orders is called........

Try to collect all the currently accepted meanings for the word 'species'. Discuss with your teacher the meaning of species in case of higher plants and animals on one hand and bacteria on the other hand.

What is the taxonomic category formed by a group of related genera?

Assertion $(A)$: $A$ taxonomic category composed of a group of related genera is called a family.
Reason $(R)$: The family $Blattidae$ includes various species of pigeons and doves.

Who published the book 'Species Plantarum' and provided a basis for the classification of plants?