115) usually lobed, and furnished either with exceptionally strong cilia, or else with very long bristles which are usually passive. However, by the retraction of the lobes that bear them they are clasped together like casting-nets to enclose prey brought into the funnel by the action of the trochal cilia. An external ring of cilia in _Floscularia mutabilis_ and _F. pelagica_ serves for swimming. In Apsilidae the margin of the disc bears neither cilia nor bristles, but is either simple and ring-like, or is produced into tentacles (Fig. 112, C). The oral funnel is probably represented in Flosculariaceae by the continuation of the small central mouth into a ciliated tube (Fig. 115, C, _tf_), open below, and hanging freely down into the crop. In all other cases the mouth is displaced, and lies in the groove and on its ventral side (except in _Conochilus_, where it is dorsal, Fig. 108, 5). In the Bdelloida the disc is prolonged into two great lobes like kettle-drums, round the posterior, external, and ventral edges of which run the trochus, cingulum, and ciliated groove (Fig. 108, 2). All three are interrupted behind in the median line; ventrally the groove widens into the oral funnel, the cingulum is continued into a sort of spout-like lower lip (Fig. 109, C, D, _l_), and the trochus is absent. The body is prolonged dorsally above the lobes into a two-jointed _proboscis_, ending in a ciliated cup overhung by two dorsal flaps: this we regard as a detached portion of the wreath. This "Bdelloid" type of wreath occurs also in Scirtopoda (Fig. 117), and in the Ploimal genera _Triarthra_, _Pterodina_, and _Pompholyx_. A simpler wreath of essentially the same type occurs in Asplanchnaceae and Melicertaceae; the disc is not prolonged into drum-shaped lobes, but is thin at the rim, where it bears the triple ciliated zone, interrupted on the dorsal median line and depressed ventrally into the oral funnel. In the Melicertidae, moreover, the disc is widened into a great plate-like extension, often beautifully lobed; and in many of the species a ciliated cup lies ventral to the lips, and is connected with the groove by a short ciliated channel on either side (Figs. 108, 4, and 116). Even the simpler wreath of Asplanchnidae is complicated by stronger lobes on either side bearing vibratile styles. The most complex discs are found in Ploima, especially in {204}_Brachionus_, _Hydatina_, and _Synchaeta_, since the groove is replaced by a zone of lappets, as above mentioned. In _Proales_ the whole face of the disc is strongly ciliated. The wreath is reduced in the parasitic genera _Drilophagus_, _Albertia_, _Balatro_, and the Seisonaceae; in _Adineta_ and _Taphrocampa_ it is only represented by a general but scanty ciliation of the disc.