The Nummus denomination
The nummus was a diminutive denomination introduced around 379 AD. It measured less than 17 mm, and weighed around 1 gram. The name nummus is almost certainly a misattribution, as recent evidence suggests that what we call a 'follis' was actually referred to as a 'nummus'.

As the disastrous 5th Century progressed, the "nummus" was to become the only bronze denomination in circulation.

By this time, the quality of Roman coinage has declined so much that official issues are frequently indistinguishable from the imitations produced by the hordes of barbarians which now occupied most of the empire.

Sic transit gloria mundi.
Nummus

(1) Constantine I AD 319-320
Obverse: IMP CONSTANTINVS AG, cuirassed bust left, wearing high-crested helmet and holding spear over right shoulder
Reverse: VICTORIAE LAETAE PRINC PERP, two Victories standing facing each other, holding between them shield, inscribed VOT PR in two lines, resting on altar ornamented with diamond pattern; five dots within, PLN in exergue
Ref: RIC 159; Sear 16296
(2) Constantine I c. AD 321-323
Obverse: CONSTAN-TINVS AVG, laureate and trabeate bust right, holding eagle-tipped sceptre
Reverse: BEAT TRA-NQLITAS, globe set upon altar inscribed VOT/IS/XX; three stars above, PLON in exergue
Ref: CT 9.05.008; RIC 267; Sear 16170
(3) Constantine I 319 AD
Obverse: CONSTANTI-NVS AVG: Bust of Constantine I, wearing high-crested helmet, cuirassed, left, spear across right shoulder and shield on left arm
Reverse: VICT • LAETAE PRINC PERP: Two Victories, winged, draped, facing each other, holding a shield inscribed VOT/PR supported by S on altar MintMark: -/-//•ΓSIS•
Ref: RIC VII Siscia 84
(4) Constantine II AD 322-323
Obverse: CONSTANTINVS IVN N C, helmeted and cuirassed bust left
Reverse: BEAT TRANQLITAS, globe on altar inscribed VOTIS XX in three lines; three stars above, PLON in exergue
Ref: RIC 287; Sear 17149
(5) Constantine II AD 330-333
Obverse: CONSTANTINVS IVN NOB C, laureate and cuirassed bust right
Reverse: GLOR-IA EXERC-ITVS, Two soldiers standing facing each other, each resting on spear and shield, two standards between them; CONSΓ in exergue
Ref: RIC 60; Sear 17338
(6) Constantius II AD 353-355
Obverse: D N CONSTANTIVS P F AVG, diademed, draped and cuirassed bust right
Reverse: FEL TEMP REPARATIO, soldier left, spearing fallen horseman, shield on ground to right; ASIS (reverse Z) in exergue
Ref: RIC 352; LRBC 1222; Sear 18271
(7) Constantius II 324-361 A.D.
Obverse: FL IVL CONSTANTIVS NOB C, laureate, cuirassed bust right
Reverse: GLORIA EXERCITVS, two soldiers flanking two standards.
Ref: RIC VII 237
(8) Crispus AD 317
Obverse: CRISPVS NOB CAES, laureate, draped and cuirassed bust right
Reverse: SOLI INVIC-TO COMITI, Sol standing left, chlamys across left shoulder, right hand raised, left hand holding up globe; S-P across fields, PLN in exergue
Ref: CT 8.09.021 (this coin); RIC 116; S...
(9) Helena AD 326-328
Obverse: FL HELENA AVGVSTA, diademed and mantled bust right, wearing necklace
Reverse: SECVRITAS REIPVBLICE, Securitas standing left, lowering branch and raising robe with right hand; SMTSΓ in exergue
Ref: RIC 159 (Constantine I); Sear 16612
(10) Johannes 423-425
Obverse: (DN IOHAN-NES PF AVG), pearl-diademed, draped and cuirassed bust right
Reverse: VICTOR-IA AVGG, Victory walking left, holding wreath and palm, Epsilon in left field
Ref: RIC X 1910
(11) Johannes 423-425
Obverse: DN IOHANN-ES PF AVG, Pearl-diademed, draped and cuirassed bust right
Reverse: SALVS REI-PVBLICAE, Victory walking left, holding trophy over shoulder and dragging captive. Epsilon in left field
Ref: RIC x 1916, Sear 21121
(12) Leo I | Verina AD 467-472
AE Nummus Unknown mint
Obverse: DN LEO (?), Head of Leo right
Reverse: Verina standing, facing, holding a transverse scepter "b-E"
Ref: RIC X 713-718
(13) Marcianus 450-457 AD
Obverse: DN MARCIANVS PF AVG, Pearl diademed, draped, and cuirassed bust right
Reverse: Monogram 1B within wreath
Ref: RIC X 535
(14) Valentinian III 425-455 AD
Obverse: DN VALENTINIANVS PF AVG, Pearl diademed, draped, and cuirassed bust right.
Reverse: VICTORIA AVGG, Victory advancing left holding wreath, T in left field
Ref: RIC 2121
(15) Zeno 476-791
AE Nummus Unknown mint
Obverse: Laureate, draped bust right
Reverse: Type 5 Monogram
Ref: RIC X 962