On the Rotiferous Genus Pedalion, &c. By Julien Dehij. 385 



tion consist in two long, winding vessels on the sides of the body. 

 At the anterior extremity exists another system of vessels, forming 

 a great vascular ring, from which branches are thrown out. As 

 regards organs of generation, the ovary alone was recognized with 

 certainty. A second small, bladder-like organ is perhaps the 

 testicle. Eggs of various sizes and stages of development were 

 contained in the ovary. The ripe eggs were light green, and were 

 carried about at the posterior end of the body. The motions of the 

 embryo, the vibration of its ciHa, and the motions of its jaws, were 

 frequently observed before leaving the egg-shell. The organs of 

 the senses consist in two round eyes, filled with a carmine-coloured 

 pigment. 



The organs of locomotion are very peculiar and complicated. 

 They consist in three pair of oars or fins. The first pair is the 

 most powerful, and takes its origin high up on the outside of 

 the abdominal face. It is conically j)ointed, has centrally on each 

 side four teeth, and divides at the tip into five pair of small plumed 

 appendages or fins. Two clearly marked muscles, striated trans- 

 versely, run through the whole length, giving off branches to the 

 appendages. The second pair of limbs is somewhat smaller in 

 all its dimensions, and is inserted deeper and more inwardly. The 

 eight teeth on the sides are shorter, and the tips only carry eight 

 appendages. 



These limbs only carry a single central muscle. The third pair 

 springs from near the middle line of the body; on its lower 

 third, it is the smallest and weakest of the whole, and only one 

 muscle is discernible in each limb. The motion of these organs 

 is very active and energetic, as well as various in direction. Not 

 only do these animals swim with great swiftness, but, just as in 

 Polyarthra, Triarthra, and others, they have the power of leaping. 

 Besides these oar-hke organs and the rotary organs, both long and 

 circular muscles aid the movements of the body. I kept the 

 creatures alive until the beginning of April." 



I advise those interested in the study of the Rotatoria to have 

 a look at these figures of Schmarda's, as no types of this class 

 of animals are more interesting from an evolutional point of view 

 than Pedalion or Hexarthra,* if this latter be really distinct 

 from it. 



* Schmarda's original work was laid before the members of the Society l)y 

 M. Deby. 



VOL. II. 2 C 



