Cannot create entry when Entry Type has Title field hidden I have created an Entry Type with the "Show the Title field" option not checked. 

When creating an entry of this type, I am given a generic "Couldn't save entry" error message.

Looking in craft.log, I see the Title field is failing validation.

2015/08/18 18:07:29 [trace] [system.CModule] Loading "templates" application component
in /Users/Sites/craft-test/web/craft/app/etc/web/WebApp.php (584)
in /Users/Sites/craft-test/web/craft/app/services/EntriesService.php (157)
in /Users/Sites/craft-test/web/craft/app/controllers/EntriesController.php (450)
2015/08/18 18:07:29 [trace] [system.db.CDbConnection] Starting transaction
in /Users/Sites/craft-test/web/craft/app/services/EntriesService.php (160)
in /Users/Sites/craft-test/web/craft/app/controllers/EntriesController.php (450)
in /Users/Sites/craft-test/web/craft/app/etc/web/WebApp.php (784)
2015/08/18 18:07:29 [trace] [system.CModule] Loading "elements" application component
in /Users/Sites/craft-test/web/craft/app/etc/web/WebApp.php (584)
in /Users/Sites/craft-test/web/craft/app/services/EntriesService.php (176)
in /Users/Sites/craft-test/web/craft/app/controllers/EntriesController.php (450)
2015/08/18 18:07:29 [warning] [application] Craft\ContentModel-&gt;title failed validation: Title cannot be blank.
in /Users/Sites/craft-test/web/craft/app/models/BaseModel.php (510)
in /Users/Sites/craft-test/web/craft/app/models/ContentModel.php (89)
in /Users/Sites/craft-test/web/craft/app/services/ContentService.php (218)
2015/08/18 18:07:29 [trace] [system.db.CDbTransaction] Rolling back transaction
in /Users/Sites/craft-test/web/craft/app/services/EntriesService.php (183)
in /Users/Sites/craft-test/web/craft/app/controllers/EntriesController.php (450)
in /Users/Sites/craft-test/web/craft/app/etc/web/WebApp.php (784)


This is on Craft Pro 2.4.2684 on Apache/2.4.10 (Unix) PHP/5.5.24.

I've tried clearing caches to no avail, and confirmed that the same issue exists with newly created Entry types with the Title field hidden.
I was using the Twig template syntax ({{varName}}) in the Title Format field on the Entry Type instead of the proper syntax ({varName}).