A: Egg of Dipylidium caninum. The individual eggs are round to oval (average size 35 to 40 µm; range 31 to 50 µm by 27 to 48 µm) and contain ...[LastModified:][Dipylidiumcaninum]MicroscopyAA:EggofDipylidiumcaninum. Theindividualeggsareroundtooval(averagesize35to40µm;range31to50µmby27to48µm)andcontainanoncospherethathas6hooklets. ImagecontributedbytheOregonStatePublicHealthLaboratory.BCB,C:EggpacketsofDipylidiumcaninum. ProglottidsofDipylidiumcaninumcontaincharacteristiceggpacketsthatareroundtoovoidandcontain5to15(sometimesmore)eggseach. TheeggpacketinBcontains8visibleeggs. TheeggpacketinC(fromthepatientdescribedinE)measures230µm×170µmandcontainsmanymoreeggsthantheaveragenumber(over30eggscanbecounted). C:ImagecontributedbytheOregonStatePublicHealthLaboratory.DED,E:ProglottidsofDipylidiumcaninum. Suchproglottids(averagematuresize12mm×3mm)havetwogenitalpores,oneinthemiddleofeachlateralmargin. Proglottidsmaybepassedsinglyorinchains,andoccasionallymaybeseendanglingfromtheanus. Theyarepumpkinseed-shapedwhenpassedandoftenresemblericegrainswhendried. Thegenitalporesareclearlyvisibleinthecarmine-stainedproglottidshowninD. TheproglottidshowninE(size15mm×3mm,preservedinformalin),waspassedbya9montholdboyinthestateofOregon (imagecontributedbytheOregonStatePublicHealthLaboratory).Macroscopic(Gross)ObservationsFF:AdulttapewormofDipylidiumcaninum. Thescolexofthewormisverynarrowandtheproglottids,astheymature,getlarger.