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: We report QTLs identified using a B6 ( host ) x A / J ( donor ) CSS panel to localize genes involved in susceptibility to pilocarpine - induced seizures .
### Output Text:
We report QTLs identified using a B6 ( host ) x A / J ( donor ) CSS panel to localize genes involved in susceptibility to <span class="chemical">pilocarpine</span> - induced seizures . 