Similis,‑e: 'Similar To' + Dative Case
P.  M. Eckel
Missouri Botanical Garden
Res Botanica
February 9, 2004


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Similis,‑e: 'Similar To' + Dative Case

P. M. Eckel


The following exercise relates to an adjective, similis,‑e, 'similar to', frequently used in the diagnosis of new taxa. It seeks to impart a degree of confidence in the use of similis in the context of the diagnosis, or diagnostic part of a description of a new taxon.


Similis,‑e is one of a group of adjectives that take their object in the dative case (rather than the nearly ubiquitous ablative).


Some readers also may not be sufficiently familiar with Botanical Latin to know that all ranks, including the species name (genus + epithet) are always declined in a Latin prose sentence. Many believe that it is not declined, but this is not true. Consequently, in a Latin sentence, if the new taxon is 'similar to' another taxon, the other, similar taxon is in the dative case.



Summary of Dative Case Endings:

(Declension = roman numerals)


          singular   plural


I.    Dat.  ‑ae      ‑is  usu. feminine nouns

I.    Dat.  ‑o       ‑is  both masc. & neuter nouns

III.  Dat.  ‑i       ‑ibus  in all genders

IV.   Dat.  ‑ui      ‑ibus  (‑ubus in lacus and tribus) usually masculine nouns

V.    Dat.  ‑ei      ‑iebus  usually feminine nouns



Some adjectives and participles in the dative (as epithets):


Dative          singular                        plural


Adj. A   longo (m) longae (f) longo (n)     ‑longis (all genders)

Adj. B   simili (all genders)               ‑similibus (all genders)

Adj. B   sinensi (all genders)              ‑sinensibus (all genders)

Part. B  protrudenti (all genders)          ‑protrudentibus (all genders)




The comparative of similis,‑e is similior (m & f) similius (n).


Dative singular: similiori (all genders)

Dative plural:   similioribus (all genders)


The superlative of similis,‑e is simillimus, simillima, simillimum.


Dative sg. simillimo (m & n) simillimae (f)

Dative pl. simillimis (all genders)


The comparative and superlative degrees also take the dative case:


Comparative: Species nova Festucae ovali affinis, sed Cypero bipartito similior, the new species is related to Festuca ovalis, however, it is more similar to Cyperus bipartitus.


Superlative: Species nova Rubo laciniato simillima, the new species is most similar to Rubus laciniatus.


Other adjectives taking the dative case are usually translated into English with the preposition 'to' or 'for'. The most notable example, after similis,‑e, is affinis,‑e, 'related to'. None of the following adjectives or participles uses a preposition in the Latin forms presented here. In fact, there is no preposition associated with the Dative case in the Latin language.


affinis,‑e (adj.B): related to.


familiaris,‑e (adj.B): familiar to, friendly to. hostilis,‑e (adj.B): hostile to, unfriendly to.


similis,‑e (adj.B) 'similar to; dissimilis,‑e (adj.B) 'not similar to' consimilis,‑e (adj.B), 'very like'.


equal to, like: aequalis,‑e (adj.B), aequus,‑a,‑um (adj.A), parilis,‑e (adj.B); par ( paris).


not equal to, unlike: inaequalis,‑e (adj.B), inaequus,‑a,‑um (adj.A), imparilis,‑e (adj.B); impar ( imparis).


next to, nearest to: proximus,‑a,‑um (adj.A with dative).


congruens,‑entis (part.B) [>congruo, ui, 3.]: to be suited to, fitted to, correspond to.


consentaneus,‑a,‑um (adj.A): agreeable to, suitable to.


conveniens,‑entis (part.A) [> L. convenio, ‑veni,‑ventum, 4. agreeing with, harmonious with, conforming to.


Note that some of these adjectives and participles also take other constructions, such as the use of the preposition 'ad' (meaning 'to') + the accusative, some may take ablative cases or the preposition 'cum' + ablative, but the examples here refer to constructions with the dative case AND NO PREPOSITION. Note that the Latin preposition 'ad', meaning generally 'to', when it is used, always takes the accusative case and no other.



EXAMPLES NAMES BELONGING TO THE FIVE DECLENSIONS (note the epithets are here fictitious hence the absence of authority names, which are usually present in the diagnostic Latin text). Authority names, usually abbreviated and never italicized, as is the convention with Latin words, are not declinable: they are not Latin nor, when routinely associated with a species name, do they have any grammatical or syntactic function in a Latin prose sentence.


0 (= undeclined). Muscari comosum (n) Note that non‑Greek and non‑Latin generic names such as Alhagi, Dipcadi, Kali, etc. are not declined: in the dative case they are spelled the same as in the nominative. Such generic names are neuter. Although the generic name may not be declined, the epithet (unless it also is from an alien language) is declined.


Muscari comoso similis, similar to Muscari comosum.


I. Genista petiolata (f)


Genistae petiolatae congruens, corresponding to Genista petiolata.


I. Alsine carinata (f)


Alsinae carinatae arcte affinis, closely related to Alsine carinata.


II. Cytisus magnificus (m)


Cytiso magnifico similis, similar to Cytisus magnificus.


II. Spartium versatile (n)


Spartio versatili affine, related to Spartium versatile. NOTE: The noun that 'affine' modifies here is understood, that is, it is assumed and not written out. In the context presented here, that noun would be the genus Spartium (the new species would be Spartium + epithet). The form of similis that modifies a neuter noun in the nominative singular would be simile (n), not similis (m & f).


II. Halimodendron bracteolatum (n)


Halimodendro bracteolato consimile, very like Halimodendron bracteolatum. NOTE: consimile, with ending ‑e, reflects a new species in the neuter genus name Halimodendron.


III. Ulex noveboracensis (f)


Ulici noveboracensi proxima, nearest to Ulex noveboracensis.


III. Ornithopus subtubulosus (m)


Ornithopodi subtubuloso conveniens, conforming to Ornithopus subtubulosus.


III. Leucostoma filiforme (n)


Leucostomati filiformi affinis, related to Leucostoma filiforme.


[I know of no genus formulated in the fourth or fifth declension, so have given examples with fructus (IV) and facies (V):]


IV. Semen fructui Solani esculenti similis, the seed is similar to the fruit of Solanum esculentum (in genitive singular).


V. Folia faciei Didmodontis rigiduli convenientia, leaves conforming to the appearance of Didymodon rigidulus (in genitive singular).




The things (nouns and modifiers of nouns) by which something else is similar are in the ablative case (capital letters).


I. Biserrula subaequans (f)


Biserrulae subaequanti HABITU SUFFRUTESCENTE congruens, corresponding to Biserrula subaequans in its suffrutescent habit.


I. Aeschynomene protrudens (f)


Aeschynomenae protrudente OVARIO SESSILI arcte affinis, closely related to Aeschynomene protrudens by the sessile ovary.


II. Astragalus panduriformis (m)


Astragalo panduriformi FOLIIS COMPLANATIS consentaneus, agreeable to Astragalus panduriformis in its complanate leaves.


II. Eremosparton vexillatum (n)


Eremosparto vexillato BRACTEIS LONGIS conveniens, conforming to Eremosparton vexillatum in its long bracts.


III. Hippocrepis mediana (f)


Hippocrepidi medianae LEGUMINE SCARIOSO affinis, related to Hippocrepis mediana by the scarious legume.


III. Fissidens ventricosus (m)


Fissidenti ventricoso cellulis inflatis basalibus similis, similar to Fissidens ventricosus by the inflated basal cells.


III. Physostigma undulatum (n)


Physostigmati undulato petallis rubris proximum, nearest to Physostigma by the red petals.




Since all families end in ‑ae (old style) or ‑aceae (new style), these are plural adjectives treated as nouns. The dative plural always ends in ‑is for all families:


Familia nova Leguminosis fructibus leguminaceis similis, sed Connaraceis atque Moringeis similior, new family similar to the Leguminosae by its leguminaceous fruits, but more similar to the Connaraceae and also the Moringeae.               





0 (= undeclined). Muscari, Muscari (n)


Hoc genus Muscari simile, this genus (neuter sing.) is similar to Muscari (indeclinable).


I.  Moringa,‑ae (f)


Hoc genus Moringae simile, this genus is similar to Moringa.


I.  Poecilanthe,‑es (f)


Hoc genus Poecilanthae affine, this genus is related to Poecilanthe.


II. Drepanocarpus,‑i (m)


Genus novum Drepanocarpo optime congruens, the new genus best agrees with Drepanocarpus.


II. Centrolobium,‑i (n)


Centrolobio corolla bilabiata arcte affinis, closely related to Centrolobium by the bilabiate corolla.


III. Eleocharis,‑itis (f)


Eleochariti maxime consentanea, to Eleocharis mostly agreeing.


III. Nymphoides,‑is (f)


Nymphoidi foliis submersis similis, similar to Nymphoides in its submerged leaves.


III. Actinomyces,‑etis (m)


Hoc genus Actinomyceti affine, this genus is related to the Actinomyces.


III. Pachyphragma,‑atis (n)


Pachyphragmati similis, similar to Pachyphragma.



NEW SUBGENUS (subgenus,-eris, a neuter word)


1. Subgenus Vignea (f)


Subgeneri Vigneae simile, similar to subgenus Vignea.


II. Subgenus Eubatus (m)


Subgeneri Eubato affine, related to subgenus Eubatus.


III. Subgenus Carex (f)


Subgeneri Carici affine, related to subgenus Carex.



NEW SECTION (section,-onis, a feminine word):


1. Dioicae


Sectio nova Dioicis similis, new section similar to the Dioicae.


II. Sylvatici


Sectio nova Sylvaticis similis, new section similar to the Sylvatici.


III. Ovales


Sectio nova Ovalibus similis, new section similar to the Ovales.


III. Tholiformes


Sectio nova Tholiformibus maxime conveniens, new section mostly agreeing with the Tholiformes.


III. Canadenses


Sectio nova Canadensibus arcte affinis, new section closely related to the Canadenses.



NOTE: when the subject of the clause or sentence is not stated (i.e. the noun to which the modifier, similis, affinis, etc. refer), the number and gender of the noun modified is often the gender of the new taxon. In the case of new species, it is the number and gender of the genus of which the new species is a member:


Rosa multiflora, sp. nov.  


Rubo laciniato affinis, related to Rubus laciniatus.     


Paspalum comosum, sp. nov.


Tritico digitali affine, related to Triticum digitale


In a basic diagnosis, the difference between taxa is often stated, as well as similarity.


Genistae petiolatae congruens, SED AB Genista lanceolata DIFFERT, corresponding to Genista petiolata BUT it differs from Genista lanceolata.


The verb 'differt', it differs, and other words expressing difference is associated with the preposition 'ab' (reduced to 'a' generally before most consonants) whose object always takes the ablative case. In these sentences, clauses and phrases, the taxon name is in the ablative case, not the dative as it would be with similis and similar adjectives and participles.




The following quiz includes some of the English sentences used above for those who might wish to translate them into Latin. The equivalent Latin (i.e. the answers) may be sought in the text above.


Similar to Muscari comosum.


Related to Triticum digitale


Similar to Cytisus magnificus.


What is the Dative Case ending for second declension singular nouns? What is the neuter singular form of the comparative of similis?


What is the singular form in the Dative Case of the participle protrudens?


Nearest to Ulex noveboracensis.


Very like Halimodendron bracteolatum.


New section mostly agreeing with the Tholiformes.


More similar to the Connaraceae and also the Moringeae.


Corresponding to Biserrula subaequans in its suffrutescent habit.


In the Latin sentence: Spartio versatili affine, related to Spartium versatile, what noun does affine refer to (modify)?


Keyword: botanical latin.