In Timsa Sutta Buddha says:
"What do you think, monks? Which is greater, the blood you have shed from having your heads cut off while transmigrating & wandering this long, long time, or the water in the four great oceans?"
Furthermore he also says:
"The blood you have shed when, being water buffaloes, you had your water buffalo-heads cut off... when, being rams, you had your ram-heads cut off... when, being goats, you had your goat-heads cut off... when, being deer, you had your deer-heads cut off... when, being chickens, you had your chicken-heads cut off... when, being pigs, you had your pig-heads cut off: Long has this been greater than the water in the four great oceans."
Doesn't this mean that there is a soul in Buddhism?