7.  The word news is always singular.  The nouns means, alms, and amends, though plural in form, may be either singular or plural in signification.  Antipodes, credenda, literati, and minutiae are always plural. Bandit is now used as the singular of Banditti.

8.  The following nouns form their plurals not according to any general rule; thus, man, men; woman, women; child, children; ox, oxen; tooth, teeth; goose, geese; foot, feet; mouse, mice; louse, lice; brother, brothers or brethren; cow, cows or kine; penny, pence, or pennies when the coin is meant; die, dice for play, dies for coining; pea and fish, pease and fish when the species is meant, but peas and fishes when we refer to the number; as, six peas, ten fishes.

    9.  The following compounds form their plurals thus:  handful,
    handfuls; cupful, cupfuls; spoonful, spoonfuls:—­brother-in-law,
    brothers-in-law; court-martial, courts-martial.

    The following words form their plurals according to the rules of the
    languages from which they are adopted.

Singular Plural. Antithesis antitheses Apex apices Appendix appendixes or appendices Arcanum arcana Automaton automata Axis axes Basis bases Beau beaux or beaus Calx calces or calxes Cherub cherubim or cherubs Crisis crises Criterion criteria Datum data Diaeresis diaereses Desideratum desiderata Effluvium effluvia Ellipsis ellipses Emphasis emphases Encomium encomia or encomiums Erratum errata Genius genii [2] Genus genera Hypothesis hypotheses Ignis fatuus, ignes fatui Index indices or indexes [3] Lamina laminae Magus magi Memorandum memoranda or memorandums Metamorphosis metamorphoses Parenthesis parentheses Phenomenon phenomena Radius radii or radiuses Stamen stamina Seraph seraphim or seraphs Stimulus stimuli Stratum strata Thesis theses Vertex vertices Vortex vortices or vortexes

[2] Genii, imaginary spirits:  geniuses, persons of great mental abilities.

[3] Indexes, when pointers or tables of contents are meant:  indices, when referring to algebraic quantities.

CASE.

Case, when applied to nouns and pronouns, means the different state, situation, or position they have in relation to other words.  Nouns have three cases, the nominative, the possessive, and the objective.

I deem the essential qualities of case, in English, to consist, not in the changes or inflections produced on nouns and pronouns, but in the various offices which they perform in a sentence, by assuming different positions in regard to other words.  In accordance with this definition, these cases can be easily explained on reasoning principles, founded in the nature of things.