Final answer:
The preferred shares held by Perkins Company in Butterfly Corporation should be treated as a non-equity interest within the consolidation process.
Step-by-step explanation:
The preferred shares should be treated as a non-equity interest within the consolidation process. When a company acquires less than 100% of another company's outstanding stock, a non-controlling interest (NCI) is created. The preferred shares held by Perkins Company represent a portion of this NCI and should be classified as a non-equity interest. The consolidation process will account for the NCI separately from the majority-owned portion of the company.