In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: The present studies were designed to clarify the role of catecholamines and pineal idolamines on ketamine - induced catatonia in the intact , pinealectomized or hypophysectomized chick and rat .
### Output Text:
The present studies were designed to clarify the role of <span class="chemical">catecholamines</span> and pineal idolamines on <span class="chemical">ketamine</span> - induced catatonia in the intact , pinealectomized or hypophysectomized chick and rat . 