They are polytrophic-meroistic ovaries formed for an anterior germarium and a basal vitellarium.
Gustavo Ferreira Martins, José Eduardo Serrão 2004, 'A comparative study of the ovaries in some Brazilian bees (Hymenoptera; Apoidea)',Papéis Avulsos de Zoologiahttp://www.scielo.br/scielo.php?script=sci_arttext&pid=S0031-10492004000300001. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
If we aim at studying the evolutionary transition from panoistic to meroistic, data on panoistic ovaries should be gathered.
Bellés Xavier, Irles Paula, Piulachs M Dolors 2009, 'Identifying genes related to choriogenesis in insect panoistic ovaries by SuppressionSubtractive Hybridization', BMC Genomicshttp://www.biomedcentral.com/1471-2164/10/206. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)