I am reading a children's book written in hiragana. I saw the opening line of the book mentioned online as being from the lyrics of a song, so I think this may be a folk song or children's song.
The first line is: いもむし ごーろごろ
I translated this as The caterpillar started to roll (with the sound effect of a large and heavy rolling object adding humor).
But then the next line confuses me completely. ひょうたん ぽっくりこ
My dictionary tells me that ひょうたん could be a contradiction or a gourd, but I don't see how either of those ideas would fit in.