User defined type within type

is there any way to have a user defined type inside another user defined type? Say you wanted a random number of schools of fish and each school has 3 fish in it, which are userdefined types. is there a way to make a school type that contains fish types in it?

Const NUM_SCHOOL_FISHES = 3

Type fishT
  Field a,b,c
End type

Type schoolT
  Field fish.fishT[NUM_SCHOOL_FISHES-1]
End Type

[EDIT] Big beat me to it

hey thanks

More fun is when you want an arbitrary number of fish in each school.