I found an image of an index record for a declaration of intent in a New York court, published online as part of the collection Alphabetical Index to Declarations of Intention of the U.S. District Court for the Southern District of New York, 1917-1950 on Fold3. The record only contains a name and two numbers:
158493
Yurkiewicz, Aleksander
299
What do the two numbers mean? Is one a page number and the other a record number? Where do I look for the record they point to?