,PEDALIONnm 133 



cliitinous lips, which may he seen constantly advancing and receding in the buceal 

 funnel, and apparently selecting the morsels which are allowed to reach the trophi. The 

 oesophagus is short, and the nearly cylindrical stomach has very thick elastic walls ; in 

 a dying specimen I have seen the food expelled, and the walls close in quite upon them- 

 selves. The gastric glands are somewhat oval ; and I think that I have seen two small 

 stalked glandular-looking bodies attached to the oesophagus. The intestine is a broad 

 short chamber with thicker walls and coarser cilia than those of the stomach. The two 

 ciliated straight processes, on the hind end of the dorsal surface, have also a glandular 

 structure and secrete a viscous fluid, by threads of which Pedalion may be found moored 

 to algae, or to the floating masses of floccose sediment. 



These processes vary greatly in length in different individuals ; they are always very 

 short in the newly hatched female, and are wanting in the male. It is unusually difficult 

 to demonstrate the vascular system, as its parts are so frequently obscured by the 

 alimentary canal and the limbs. There are two lateral canals, each commencing in a 

 plexus close to an eye and bearing a vibratile tag. Hence the canal runs down to a 

 second plexus, halfway down the body, with two vibratile tags ; and, skirting the side, 

 finally unites with the cloaca. There is no contractile vesicle. The ovary requires no 

 notice. Pedalion carries its extruded egg attached to its posterior extremity till it is 

 hatched. Of the large oval female eggs only one at a time is so carried ; the small, 

 round male eggs are carried in clusters : the eggs of different sexes are never present 

 together. The newly hatched female resembles its mother, and passes through no 

 change but that of growth. The muscular system is very greatly developed. There 

 are at least forty striated muscles arranged in pairs of elevators and depressors, not mere 

 repetitions of each other like the muscles of a caterpillar, but very various in shape and 

 arrangement, and obviously intended for different duties. Figs. Id, le, If show these 

 pairs very carefully drawn and, with the printed explanation facing PI. XXX., render any 

 detailed account superfluous. The nervous ganglion lies closely applied to the dorsal 

 side of the buceal funnel, and has above it two eyes, widely apart and close to the surface 

 of the corona ; one in each of its lobes. They are clear refractive spheres set on plates 

 of red pigment. Nerve-threads pass from the ganglion to lateral rocket-headed antennae, 

 one on each shoulder ; and another nervous thread supplies a similar antenna which 

 moves up and down in a protuberance on the dorsal median line (figs, la, 16) just 

 behind the dorsal gap in the ciliary wreath. 



The male (figs. Ih, Ik) is the merest caricature of the adult female. The large, 

 shapely corona, with its flowing curves has become a ciliated knob ; the six limbs, with 

 their fan-shaped plumes, have been altered into three little stumps, with a bristle or two 

 at the end of each ; even the huge ventral limb has vanished, and the whole creature 

 has shrunk up to barely one-fifth of the length of the adult female. It swims very dif- 

 ferently from its mother ; for it spins constantly round its own length, like a joint on a 

 spit, while at the same time moving forward. Now and then it jerks its side limbs, and 

 it uses them to free itself from its shell. There are two longitudinal muscles for retract? 

 ing the head and a pair of red eyes, but I could discover no other internal organs except 

 the testis and penis. This latter I have seen protruded to a length quite equal to that 

 of half the animal. * 



Length. Female, corona and body, -j-^ inch ; from corona to end of ventral limb, 

 excluding setae, ^ inch : male, r |^ inch. Habitat. Clifton (C.T.H.) ; Birmingham 

 (T.B.) ; warm water-lily tank in the Duke of Westminster's gardens at Eaton, arid 

 ponds in the neighbourhood of Chester (Mr. Thos. Shepheard) : very rare. 



The only other Kotiferon in this Order is Hexarthrapolyptera (PL XXX. fig. 2), 1 which 



was discovered by Dr. Schmarda in some brackish water near El Kab in Egypt, in March 



1853. He describes the body as a blunt cone with a right and left group of cilia on its 



broad end. The trophi resemble those of Triarthra. The stomach is short and broad ; the 



1 Copied from Dr. Schruarda's fig. 1, Zur Naturgescli. Agyptens, Taf. iii. 



