As you probably know castor plant is one of the most poisoned plants on Earth! This is because it has substance called ricin! Only thing that can be used for human consumption is oil from cold pressed castor seed. So only thing that is interesting for humans are castor plant seeds! Seed is locked inside castor "fruit". Fruit is cocoon that has three sections. It can be elliptic or round shape. Fruit has spikes and depending on sort of castor plant they can be long or short! When it reaches mature state, fuit will break up and seed will fall on ground. From total fruit weight on seed weight goes about 70%. Seeds have round shape and they look like beans!
Castor seed cannot be consumed in this form because inside of them is also ricin - one of the deadliest poisons on planet! Lethal dosage for average human is just few seeds! For castor oil too use from castor seed, seed has to be cold pressed! Only after this you can consume castor oil!