_Sing._ _Plur._ | _Sing._ _Plur._ | Calcul_us_ calcul_i_ | Polyp_us_ polyp_i_ Coloss_us_ coloss_i_ | Radi_us_ radi_i_ Convolvul_us_ convolvul_i_ | Ranuncul_us_ ranuncul_i_ Foc_us_ foc_i_ | Sarcophag_us_ sarcophag_i_ Geni_us_ geni_i_ | Schirrh_us_ schirrh_i_ Mag_us_ mag_i_ | Stimul_us_ stimul_i_ Nautil_us_ nautil_i_ | Tumul_us_ tumul_i_. Oesophag_us_ oesophag_i_ | (_c_).--_Where the Singular termination _-um_ is changed in the Plural into _-a__:-- _Sing._ _Plur._ | _Sing._ _Plur._ | Animalcul_um_ animalcul_a_ | Mausole_um_ mausole_a_ Arcan_um_ arcan_a_ | Medi_um_ medi_a_ Collyri_um_ collyri_a_ | Memorand_um_ memorand_a_ Dat_um_ dat_a_ | Menstru_um_ menstru_a_ Desiderat_um_ desiderat_a_ | Moment_um_ moment_a_ {104} Effluvi_um_ effluvi_a_ | Premi_um_ premi_a_ Empori_um_ empori_a_ | Scholi_um_ scholi_a_ Encomi_um_ encomi_a_ | Spectr_um_ spectr_a_ Errat_um_ errat_a_ | Specul_um_ specul_a_ Gymnasi_um_ gymnasi_a_ | Strat_um_ strat_a_ Lixivi_um_ lixivi_a_ | Succedane_um_ succedanea. Lustr_um_ lustr_a_ | (_d_).--_Where the singular termination _-is_ is changed in the Plural into _-es__:-- _Sing._ _Plur._ | _Sing._ _Plur._ | Amanuens_is_ amanuens_es_ | Ellips_is_ ellips_es_ Analys_is_ analys_es_ | Emphas_is_ emphas_es_ Antithes_is_ antithes_es_ | Hypothes_is_ hypothes_es_ Ax_is_ ax_es_ | Oas_is_ oas_es_ Bas_is_ bas_es_ | Parenthes_is_ parenthes_es_ Cris_is_ cris_es_ | Synthes_is_ synthes_es_ Diaeres_is_ diaeres_es_ | Thes_is_ thes_es_. THIRD CLASS. _Words wherein the Plural is formed by inserting _-e_ between the last two sounds of the singular, so that the former number always contains a syllable more than the latter_:-- _Sing_. _Plur_.