. A manual of zoology. Zoology. ROTIFERA. 29c 12. The embryo, in the intermediate host, becomes enc}'sted and changes directly to a scolex (pleurocercoid) or into a bladder worm (cysticercus) which produces internally one or more scolices. 13. The scolex is freed from its cyst when taken along with food into the stomach of the proper host, and then acquires the capacity of development into a tapeworm. 14. In man occur as cysticerci Tcenia echinococcus (adult in dog) and T. solmm; as adults Tceiiia solium (cysticercus in pigs), T. saginata (cysticercus in cattle), and Botlirioceplialus latiis (
. A manual of zoology. Zoology. ROTIFERA. 29c 12. The embryo, in the intermediate host, becomes enc}'sted and changes directly to a scolex (pleurocercoid) or into a bladder worm (cysticercus) which produces internally one or more scolices. 13. The scolex is freed from its cyst when taken along with food into the stomach of the proper host, and then acquires the capacity of development into a tapeworm. 14. In man occur as cysticerci Tcenia echinococcus (adult in dog) and T. solmm; as adults Tceiiia solium (cysticercus in pigs), T. saginata (cysticercus in cattle), and Botlirioceplialus latiis (pleurocercoid in fish). 15. The Nejiertik"! are distinguished by a complete alimentary canal with anus, and a proboscis dorsal to the digestive tract. PHYLUM V. ROTIFEExV (ROTATORIA). The aquatic wheel animalcules, or Rotatoria, are among the smallest Metazoa, and can be distinguished from the Infusoria, which they resemble in habits, only by the microscope. The body is divisible into three regions, head, trunk, and tail. The trunk is covered by a tough cuticle into which head and tail can be. Fig. 3r>7.—Diagram of rotifer- (After Delage et Herouard ) /», brain: fc, flame ceU; f/(/, gastric gland; ?, intestine: iii, niastax; <n\ ovary; pij^ pedal gland: /t, pulsat- ing vesicle of excretory system; «, stomach. retracted. The tail or ' foot' is often composed of rings which can be telescoped into each other and which by their superficial resem- blance to segmentation formerly led to the association of the roti- fers with the Arthropoda. The last tail ring often bears a pair of pincer-like stylets which together with adhesive glands enable the aiiimal to adhere to objects. The head has the most delicate eiiticle and is expanded in front to a trochal disc, an apjiaratus of varying appearance, wliich is surrounded liy a ring of cilia of use in swimmin<r and also in directing food to the ventral mouth. The. Please note that these images are extracted from scanned pa
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