The book contains the first known reference to the unicorn, ostensibly an ass in India that had a single 1.5 cubit horn on its head, and introduces the European world to the talking parrot, and falconry, which was not yet practiced in Europe. Among the information apparently conveyed in the book :
The Indus river is identified, and described as being up to twenty miles across.
India is heavily populated, more than the rest of the world combined
While monkeys were well known in the Mediterranean, unusual types are described for India, including a tiny breed with a tail six feet in length
Indian dogs the size of lions
Gigantic mountains
The martikhora, a red creature with a face like a man's, three rows of teeth, and a scorpion's sting on its tail. This is the earliest known Western reference to the manticore.
Detailed descriptions of Indian customs, proclaiming them very just and honorable.
Palm and date trees three times the size of those in Babylon
Legacy
Ctesias' books contains such a mix of obviously dubious apocrypha among its truths that it was sometimes mocked by subsequent authors as a source of wild yarns and myths. In the second century AD, the satirist Lucian depicted Ctesias as being condemned to a special part of hell reserved for those who spread wild lies during their lifetimes. Indica apparently included such anecdotes as the description of a race of one-legged people called the Monosceli, another whose feet were so big they could be used as umbrellas, men with tails like satyrs, and claimed that people in the actual land of Serica were 18 feet tall. Lucian's own similar book, A True Story, was presented as a satire of Indica, including an introduction that calls Ctesias and other similar authors inexperienced liars. Lucian states that he, himself, will now present a similar lie, but unlike his predecessors, he is at least honest enough to state this plainly up-front. Conversely, the book did serve as the original source for a great deal of actual knowledge about the East that appears to have been completely absent in Western literature. Though only fragments exist today, its probable contents are very well-known because they were the main reference for Mediterranean knowledge of India, for centuries, and therefore are cited and quoted by many ancient authors whose works do survive to this day.