Well, at long last, we have finally resolved the matter of "humps". Perhaps now we can move on to more savory subjects of mnemonic learning such as the origins of these camels.

Dromedary: Known as "the arabian camel.
Bactrian: Rearrange the letters in "a bactrian" to read "ain't arab"
Further, if challenged, I can prove mnemonically that "ain't" is proper english.

Incidentally; In mid last century rural Alabama it was quite acceptable in polite society to remark.. "Mary Ellen finally had her youn'un. It was a little nine pound humper". Then and there, people were more colorful and more direct.