If you're a naturalist, botanist or just a lover of old, dusty books, you'll be delighted to know that one of the world's largest open access digital archives is now available for you to peruse its 55 million pages of literature and 150,000 illustrations of life here on Earth.

Called the Biodiversity Heritage Library (BHL), it's a worldwide consortium of natural history, botanical, research and national libraries coming together to "address a major obstacle to scientific research: lack of access to natural history literature."

Many of their images are in the public domain, meaning you may use them without risking copyright infringement. From lithographs of wild animals in London's Regent Park in the mid-19th century to pomology (the study and cultivation of fruit) to the ancient fauna of Nebraska to esoteric anthropological treatises in Charles Darwin's personal collection, you're sure to lose a few hours digitally combing through these ancient tomes.

These illustrations below are just a fraction of the unusual flora and fauna you'll find rifling through this global biodiversity community. Whether you're looking for myriapods or mermaids, you'll be sure to find your biology thesis or next tattoo inspiration (hey, you never know!) in their treasure trove of illustrations.

The glyptodon

lithograph of giant armadillo glyptodon
"Their only enemies seem to be the monkeys," says the author of "Extinct Monsters" about giant armadillos. (Photo: Chapman & Hall [CC by 2.0]/Flickr)

Before we were spoiled by Disney cartoons and cutting-edge photo technology, we had to imagine monsters in our minds. Author and clergyman Rev. H.N. Hutchinson was up to the task, featuring sloths, mammoths, dinosaurs and other "monsters" in his 1892 book, including the now-extinct glyptodon (a giant armadillo). An excerpt from his preface is below:

"The object of this book is to describe some of the larger and more monstrous forms of the past — the lost creations of the old world; to clothe their dry bones with flesh, and suggest for them backgrounds such as are indicated by the discoveries of geology: in other words, to endeavour, by means of pen and pencil, to bring them back to life. The ordinary public cannot learn much by merely gazing at skeletons set up in museums. One longs to cover their nakedness with flesh and skin, and to see them as they were when they walked this earth."

The thylacine

Joseph Wolf was a German lithographer who came to London to be the Zoological Society's resident artist in 1861. Regent's Park, now called the London Zoo, was founded in 1828 for "the purpose of scientific observation of wild animals from all parts of the British Empire."

Since Wolf had only sketched animals in the wild before, he found it challenging to show the animal in their natural state, when in reality they were enclosed in cages. Philip Sclater, secretary of the Zoological Society of London for 42 years, provided notes with each animal, an excerpt of which is below:

"While in the hands of Mr. Gunn, the thylacines were fed exclusively on mutton, upon which diet they continued to thrive during the voyage, as well as after their arrival in London. The thylacine originally preyed on the kangaroos and bandicoots, but since the introduction of sheep into the colony, it has become more addicted to attack the sheep-folds. Perpetual war is therefore waged against it by the Tasmanian shepherds, whose determined persecution must eventually lead to its extinction."

The sea serpent

a sketch of a large sea monster in the ocean circa 1890s
The 1892 book "The Great Sea-Serpent" is a critical treatise featuring 187 reported appearances of mythical creature. (Photo: Leiden: E. J. Brill [public domain]/Flickr)

This 1892 book is dedicated to ship owners, sea captains and zoologists, with the author, A.C. Oudemans, collecting hundreds of appearances and sketches of the supposed sea serpents spotted throughout the world's seas and oceans. This particular serpent, spotted near Puerto Rico (then a colony of Spain), apparently gave off quite a memorable smell, as one ship-goer recalled:

"It caused a stench enough to make one ill; this smell, which hung about us for more than half an hour, was like that of a fermentation by heat on a large scale of the house of Lesage, the great gatherers of Asnieres, mingled with that of a dozen of charcoal-black works of Billancourt. To neutralize it, all the shops of several of our best perfumers would be wanted."

The manticore

an illustration of a mythical man-creature called a manticore
The myth of the manticore has Persian origins, similar to the Egyptian sphinx. (Photo: John C. Nimmo [public domain]/Flickr)

The 1890 book "Curious Creatures in Zoology" is sure to give you plenty of nightmare material. The author, John Ashton, implores his readers to take everything with a grain of salt: "It is simply a collection of zoological curiosities, put together to suit the popular taste of today, and as such only should it be critically judged." The manticore, featured above, is featured alongside centaurs, unicorns, werewolves and other fabled creatures.

Ashton writes: "It is as large and rough as a lion, and has similar feet, but its ears and face are like those of a man; its eye is grey, and its body red; it has a tail like a land Scorpion, in which there is a sting; it darts forth the spines with which it is covered, instead of hair, and it utters a noise resembling the united sound of a pipe and a trumpet; it is not less swift of foot than a stag, and is wild, and devours men."

The kraken

illustration of sea kraken attacking ship
This sea monster is a staple in sailors' superstitions. (Photo: W. H. Lizars Edinburgh [CC BY-NC-SA 2.0]/Flickr)

"The Naturalist's Library" by Sir William Jardine also delves into the imaginary creatures of the 19th century. The kraken was a popular sea monster known for allegedly terrorizing sailors in Scandinavian folklore, though in reality, it most likely came from sightings of giant squids.

Jardine writes about the kraken with a healthy bit of skepticism: "The statements of the Ancients concerning this animal are so exaggerated, that we will not try the patience of our readers by copying them. The belief in this monster is, however, universal among the sailors and fishermen of the Norwegian coast, and it has been alluded to by all the Scandinavian writers from the earliest period down to the present day."

The sea monk

16th century illustration of legendary sea monk creature
All of 16th century Europe was fascinated by the strange animal called a "sea monk" for its human head and coat of scales. (Photo: Apud C. Stephanum Parisiis [CC by 2.0]/Flickr)

Sea monks have been referenced in literature since the 12th century, though no one is exactly sure where its origins lie. According to naturalists in the 16th century, this alleged creature was captured in the Øresund, a strait between the island of Sjælland (Denmark) and Sweden around 1540. Zoologists now believe it could have been a giant squid, walrus or an angel shark species.

In a BHL blog post about the legend of sea monks, Grace Costantino speculates: "Identifying an origin species for the monkfish is further complicated by the fact that these representations were also possibly influenced by religious tensions of the period. The association between clerical figures and monsters may be seen as a commentary on these tensions, with religious elements being imposed on natural entities."

The dragon

Ulisse Aldrovandi was an Italian naturalist in the 16th century and was considered the driving force behind Bologna's botanical garden, one of the very first in Europe. If you can read Latin, he left behind a wealth of natural history books and specimen collections, including one book entirely dedicated to dragons and serpents.

He apparently claimed to even keep a dragon in his museum at the bequest of his cousin, Pope Gregory XIII. Today, the BHL has more than 15 of his works available online, ranging from chicken embryo incubation to Roman statues to pharmacopoeia.

Lindsey Reynolds ( @https://twitter.com/LindseyKateR ) takes an epicurean and academic approach to foodways, but she also writes about so many other things, including art, psychology and how to live an environmentally responsible life.