Hippopotamus hippopotamus is the scientific name for what we all know as the hippopotamus.
This drawing was rendered in pastel but using a cold press water color paper. Cold press paper has a strong "tooth" - that is, pretty good size bumps on the surface - that add texture to the areas of the color. Actually this paper had a bit more tooth than was originally wanted and it ate up a lot of the pastel sticks. Another new-fangled type of pastel paper is "sanded" paper. That really eats up the sticks.
Like the emerald toucanet on the next page, this particular beastie was found residing the Philadelphia Zoo, one of the oldest zoological gardens in the United States and at one time a customer of the legendary Frank "Bring-'Em Back Alive" Buck.
The plural of hippopotamus is a bit of a controversy. You'll see both hippopotami and hippopotamuses in dictionaries, but it seems that treating the singular as the plural should be OK too. In fact, it sounds better. "I saw a herd of hippopotamus swimming in the river". Nothing wrong with that.
Ultimately the word is from the ancient Greek, ἱπποπόταμος (pronounced unsurprisingly as hippopotamus), and the plural is, ἱπποπόταμοι, which is yes, hippopotamoi.
Hippos originally lived through all of Africa wherever there was water and even made it up the Nile to the Delta. Now they only are found in pockets south of the Sahara, although they are widely dispersed and range as far west as Senegal and Gambia. But they are no longer found in Egypt.
Hippopotamus are far from the placid giants you see lolling about in the African rivers. They are cantankerous and aggressive and will chase people if they see fit. The number of people killed each year varies with the source, but the current numbers you see bandied about are maybe 300, or perhaps 3000, or maybe even as high as 33,000. The later is certainly too high and the 3000 number is what gets bandied about most on the Fount of All Knowledge. Of course like most of what you read on the Fount, there are usually no references given except another web page.
Hippos are dangerous, but not the most dangerous of the beasties. Statistics are iffy and uncertain, but around 30,000 people each year die by bites of venomous snakes, and there's one animal that is responsible for over 120,000 deaths per year in the world - and almost 10,000 in the United States alone!
Hippopotamus have been subject of art for millennia, and you can see a 3D work of hippopotamus art - that is 3D art representing a hippopotamus, not 3D art created by a hippopotamus - if you click here.