Full Idea
Atomism is the most common version of corpuscular prime matter, but it is not the only option. Indeed, atomism neither entails nor is entailed by the combination of corpuscularianism and the substratum thesis.
Gist of Idea
Atomism is the commonest version of corpuscularianism, but isn't required by it
Source
Robert Pasnau (Metaphysical Themes 1274-1671 [2011], 03.2)
Book Reference
Pasnau,Robert: 'Metaphysical Themes 1274-1671' [OUP 2011], p.41
A Reaction
The point is that the corpuscles may be endlessly divisible (which Lewis called 'gunk').