Abstract: Larvae of ants are fed either with regurgitated material from the worker's crops, including glandular secretions, or with solid food particles, or both. Feeding of larvae of Leptothorax acervorum (Fabricius, 1793) was studied with behavioral observations, with dyed food, and with Sem pictures of larvae. Young larvae of 1st and 2nd instars receive only regurgitated food, whereas 4th, and rarely also 3rd instar larvae also ingest solid food particles. The 4th instar larvae have specialized rough cuticular structures on the ventral side of four anterior segments, i.e., the meso- and metathorax and the abdominal segments I and II. Evidently these structures help to keep food particles in place while manipulated and ingested by the larva. The entirety of the structures may be homologous to other specializations of the anteroventral region such as food basket, or the praesaepium, but probably not the trophothylax, found in larvae of other ants, though various differences in shape and localization justify a new term, the "mensarium".