Hrabanus Maurus (ca. 780-856), abbot of Fulda and Archbishop of Mainz, was theological and pedagogical writer. He was born at Mainz about 776 (or possibly 784) and died near there in 856. His name, which is spelled in various ways (Hrabanus, Rabanus, Rhabanus, Reabanus, Raban, Rabano), is connected with Old High German hraban, "raven"; "Magnentius", which sometimes appears before his surname, Maurus, is probably related to his residence in Mainz. At an early age he became a Benedictine monk at Fulda. In 802 he went to Tours to study theology and the liberal arts, under the great scholar Alcuin, from who he received the surname Maurus after the favorite disciple of St. Benedict. After a year of study, he was recalled to Fulda, where he taught at the monastic school and eventually became head-master. In 814 he was ordained as a priest; in 822 he became abbot of the monastery. Under Abbot Hrabanus, the monastery flourished, becoming a renowned seat of learning in the Frankish kingdoms. Between 840 and 847 Hrabanus became embroiled in royal political struggles, resigned as abbot, and fled from Fulda. In 847, after a reconciliation with the king, he was appointed Archbishop of Mainz.

Hrabanus was said to be the most learned man of his age. His knowledge of scripture, patristics, canon law and liturgy was without compare. The scope of his writing extended over the entire field of sacred and profane learning as then understood. He wrote commentaries on nearly all the books of the Old Testament, as well as the Gospel of Matthew and the Pauline Epistles. He also wrote more secular works such as De computo, a treatise on numbers and the calendar; the Excerptio de arte grammatica Prisciani, a treatise on grammar and his famous encyclopedia, De rerum naturis.

De rerum naturis (On the Nature of Things), also known as De universo, is an encyclopedia in 22 books, covering a large range of subjects. It was written between 842 and 847. Hrabanus' stated intent was to compile an encyclopedic handbook for preachers. He drew on earlier sources for his information, particularly the Etymologiae of Isidore of Seville, but the organization of the material was his own invention.

Book 8 is on animals. It is divided into seven chapters: De bestiis ("beasts", mostly mammals); De minutis animantibus (small animals); De serpentibus (serpents, reptiles); De vermibus ("worms", mostly insects); De piscibus (fish); De avibus (birds); De minutis avibus (small birds). The chapters and the animals in them are (based on  Schipper) (this list is preliminary and may not be entirely reliable):

Chapter 1: De bestiis - On beasts

Leonis (lion)

Tigris (tiger)

Panter (panther)

Pardus (pard)

Rinocerota (monocerus and unicorn)

Elefantem (elephant)

Gripes (griffin)

Camaeleon (chameleon)

Linx (lynx)

Castores (beaver)

Ursus (bear)

Lupus (wolf)

Canis (dog)

Vulpis (fox)

Simiae (ape)

Enidros (hydrus)

Dracontius (dragon)

Musio (cat)

Chapter 2: De minutis animantibus - On small animals

Mus (mouse)

Mustela (weasel)

Talpa (mole)

Glires (?)

Hiritius (hedgehog)

Grillus (?)

Formica (ant)

Ranae (frog)

Chapter 3: De serpentibus - On serpents

Cerastes (cerastes)

Draco major (dragon)

Aspis (asp)

Ipnalis (hypnalis, another kind of asp)

Bailiscus (basilisk)

Scorpio (scorpion)

Vipera (viper)

Enidris (hydros?)

Celidros (?)

Salamandra (salamander)

Chapter 4: De vermibus - On worms

Areana (spider)

Cantarida (?)

Multipes (multiped)

Limax (?)

Bombices (?)

Eruca (?)

Teredonas (termite?)

Tinea (?)

Lumbricus (?)

Ascaridae (?)

Tarmus (?)

Ricinus (?)

Usia (?)

Chapter 5: De piscibus - On fish

Crocodrillus (crocodile)

Mullus (?)

Mugilis (?)

Anguillae (sea snake?)

Draco marinus (sea dragon)

Mure (?)

Concae, Cocleae (?)

Murice (?)

Chapter 6: De avibus - On birds

Aquila (eagle)

Vultur (vulture)

Grues (crane)

Ciconiae (stork)

Olor (swan)

Strutio (ostrich)

Ardea (heron)

Fenix (phoenix)

Cinomolgus (cinnamologus)

Psittacus (parrot)

Alcion (kingfisher)

Onacrotalus (bittern)

Vespertilio (bat)

Noctua (owl)

Bubo (owl)

Lucina (nightingale)

Ulala (owl?)

Graculus (jay)

Picus (woodpecker)

Pavo (peacock)

Gallus (cock)

Anser (goose)

Mergis (merganser?)

Fulica (coot)

Turtur (turtledove)

Columba (dove)

Perdix (partridge)

Coturnices (quail)

Passer (sparrow)

Pellicanus (pelican)

Nocticorax (owl)

Garrula (?)

Hirundo (swallow)

Corvus (raven)

Cornix (crow)

Milvus (kite)

Accipiter (hawk)

Uppupa (hoopoe)

Chapter 7: De minutis avibus - On small birds

Apes (bee)

Spines (?)

Scrabrones (?)

Locusta (locust)

Musca (?)

The books and chapters of the De rerum naturis are listed below (based on  Schipper).

Book 1: On God and angels

De deo; De filio dei; De spiritu sancto; De eadem trinitatis; De angelis

Book 2: On man, the patriarchs, the status of man

De hominibus qui quodam praesagio nomina acceperunt; De patriarchis et ceteris eiusdem aetatis hominibus

Book 3:

De aliis quibusdam viris, siue faeminis quorum nomina in vetere testamento scripta leguntur; De prophetis

Book 4: People of the New Testement, martyrs, clerics, monastics, heretics

De personis quae ad novum testamentum pertinent; De martiribus; De Aeclesia et sinagoga; De religione et fide; De clericis; De monachis; De ceteros fidelibus; De heresi et scismate; De heresibus; De diffinitionibus recte fidei et aeclesiasticorum dogmatum

Book 5:

De sanctis scripturis hoc est vetere et novo testamento; De auctoribus eorundem librorum; Brevis annotatio quae indicat quid in sanctis canonicis; De bibliotheca; De opusculorum diversitate; De canonibus evangeliorum; De canonibus conciliorum; De heresi et scismate; De heresibus; De hostiis holocaustis atque sacrificiis et quid eorum species singulae significent; De sacramentis divinis ubi quid in his homini; De exorcismo; De simbolo; De oratione et ieiunio; De penitentiae satisfactione atque ex homologesi

Book 6:

De homine et partibus eius; De situ et habitu corporis humani; Quomodo humana membra asscribantur diabolo

Book 7:

De aetatibus hominis; De generationis prosapia; De ordinibus filiorum; De agnatis et cognatis; De coniugiis; De morte; De portentis; De pecoribus et iumentis

Book 8: On animals

De bestiis; De minutis animantibus; De serpentibus; De vermibus; De piscibus; De avibus; De minutis avibus

Book 9: On astronomy - the world and the heavens

De mundo et IIII plagis ipsius; De athomis; De elementis; De caelo; De partibus caeli; De ianuis caeli; De cardinibus; De lucae; De luminaribus; De sole; De luna; De sideribus; De Pliadibus et Arcturo; De arcturo; De Orione et Hiadibus; De Lucifero; De vespere; De aere; De nubibus; De tonitru et fulgure atque coruscationibus; De arcu caelesti; De igne; De pruna; De carbonibus; De cineribus; De ventis; De aura et altano; De turbine; De procellae

Book 10: On time and the calendar

De temporibus; De momentis; De horis; De diebus; De partibus diei; De nocte; De septem partibus noctis; De tenebris; De ebdomadibus; De mensibus; De vicissitudinibus temporum IIII; De anno; De saeculo; De sex aetatibus saeculi; De festiuitatibus; De sabbato; De dominico die

Book 11: On water - oceans, rivers, floods

De diversitate aquarum; De mari; De oceano; De mediterraneo; De rubro mari; De abysso; De estibus vel fretis; De lacis et stagnis; De fontibus; De fluminis; De torrentibus; De puteis; De gurgitibus; De pluviis; De gutta; De nive; De glacie; De pruina et grandina; De rore; De nebula; De diluviis

Book 12: On geography - the regions of the Earth, the globe, paradise

De terra; De orbe; De paradiso; De regionibus; De insulis; De promontoriis

Book 13: On geography - mountains, valleys, deserts

De montibus; De collibus; De vallibus; De campis; De saltibus; De locis; De confragosis locis; De lustris ferarum; De lucis; De desertis locis; De deuiis locis; De amoenis locis; De apricis locis; De lubricis locis; De estiuis locis; De naualibus locis; De litore; De specu; De hiatu; De profundo; De baratro; De erebi profunditate; De loco cociti

Book 14: On architecture and building

De aedificiis publicis; De portis; De uiis; De plateis; De cloacis; De foro; De curia; De pretorio; De gymnasio; De capitolio; De arcibus; De amphitheatro; De faro; De thermis; De balneis; De politerio; De thabernis; De macello; De carcere; De habitaculis; De aedificiis sacris; De aditibus; De parietibus aedificiorum; De repostoriis; De officinis; De munitionibus; De tentoriis; De sepulchris; De aedificiis rusticis; De agris; De mensuris agrorum; De itineribus

Book 15: On the liberal arts

De philosophis gentium; De poetis; De Sibillis; De magis; De paganis; De diis gentium

Book 16: On language

De linguis gentium; De gentium vocabulis; De regnis miliaeque vocabulis; De civibus

Book 17: On geology - stones, minerals, gems, metals

De pulueribus et glebis terra; De glebis et aquis; De lapidibus vulgaribus; De lapidibus insignioribus; De marmoribus; De ebore; De gemmis; De margaretis; De christallis; De vitro; De metallis; De auro; De aere; De auricalco; De electro; De stagno; De plumbo; De ferro

Book 18: On number, music, medicine

De ponderibus; De mensuris; De numero; De musica et partibus eius; De medicina et morbis

Book 19: On agriculture

De cultura agrorum; De frumentis; De leguminibus; De vitibus; De arboribus; De propiis nominibus arborum; De aromaticis arboribus; De herbis aromaticis, siue communibus; De oleribus

Book 20:

De bellis; De triumphis; De instrumentis bellicis; De bucinis et tubis; De armis; De gladiis; De hastis; De sagittis; De faretris; De fundis; De loricis; De clippeis; De loricis; De galeis; De foro; De spectaculis; De ludo gimnico; De generibus gimnicorum; De saltu; De cursu; De iactu; De uirtute; De luctatione; De palestra; De agone; De generibus agonum; De ludis circensibus; De circis; De aurigis; De curru; De equis quibus curritur; De septem spatiis; De equitibus; De peditibus; De coloribus equorum; De theatro; De ferali certamine; De horum execratione ludorum;De navibus; De partibus navigum et armamentis; De velis; De funibus; De retibus; De fabrorum fornace

Book 21: On textiles and clothing

De fabricis pariete; De dispositione; De constructione; De venustate; De laqueariis; De crustis; De lithostrotis; De plastis; De pictura; De coloribus; De instrumentis aedificiorum; De lignariis; De laneficii inventione; De vestibus sacerdotum; De diversis nominibus vestimentis; De proprio quarundam gentium habitu; De palleis virorum; De palleis feminarum; De stratu, et reliquis vestibus, quae in usu habentur; De lanis et lino; De instrumentis vestium; De ornamento; De anulis; De cingulis; De calciamentis

Book 22:

De mensis et escis; De potu; De vasis escariis; De vasis potatoriis; De vasis vinariis sive aquariis; De vasis oleariis; De vasis coquinariis et pistoriis; De vasis repositoriis; De canistro; De vasis; De lectis et sellis; De vehiculis; De reliquis quae in usu habentur; De instrumentis rusticis; De instrumentis hortorum; De instrumentis equorum

Other medieval encyclopedias:

Bartholomeus Anglicus : De proprietatibus rerum

Isidore of Seville : Etymologies

Lambert of Saint-Omer : Liber floridus

Brunetto Latini : Li Livres dou Tresor

Jacob van Maerlant : Der Naturen Bloeme

Konrad von Megenberg : Das Buch der Natur

Thomas de Cantimpré : Liber de natura rerum