Dipylidium adult

The inset in this photo shows an enlargement of the scolex. Two of the prominent suckers are visible, and at the tip of the rostellum is a circle of small hooks. All these aid in attachment to the host.

The main part of the photo shows four regions of the strobila of a single adult worm. Note the great variation in proglottid sizes. At the top is the scolex and a region of immature proglottids. The centre two pieces are mature proglottids in different stages of development. Not much detail is visible, but you can see the paired ovaries in each proglottid. This tapeworm has two complete sets of male and female reproductive structures in each proglottid. The segment at the bottom gravid proglottid. The small, clear spheres within the gravid proglottid are egg capsules, each one containing several eggs. The egg capsule is a piece of the worm's uterus which breaks down and surrounds groups of eggs. After the gravid proglottid is shed and ruptures in the external environment, the egg capsule provides an additional layer of protection against conditions in the external environment, and also is a convenient size for ingestion by the intermediate host.