THE FEEDING MECHANISM OF SOME FRESHWATER CYCLOPOID COPEPODS

Summary. An account is given of the feeding mechanism of some freshwater cyclopoid copepods. Chance encounter appears to play an important part in the finding of food in both carnivorous and herbivorous species, but the chemoreceptor organs apparently utilized by the herbivores to discriminate between edible and inedible particles may help to some extent in food seeking. The structure, arrangement, and method of operation of the various mouthparts are described, and the raptatory method of feeding of the cyclopoids is demonstrated. The route taken by the cyclopoids towards a parasitic mode of life is considered from a functional standpoint. The phylogeny of the Cyclopoida and Calanoida is discussed. A carnivorous diet is considered to be the primitive diet of the Cyclopoida. A change from a carnivorous to an algal diet may have been of considerable importance in the adaptive radiation of the group.

[1]  G. Fryer.  The food of some freshwater cyclopoid copepods and its ecological significance. , 1957 .

[2]  A. Hasler.  Odour Perception and Orientation in Fishes , 1954 .

[3]  T. J. Walker,et al.  Detection and Discrimination of Odors of Aquatic Plants by the Bluntnose Minnow (Hyborhynchus notatus) , 1949, Physiological Zoology.

[4]  R. Gurney.  XLIV.—Some remarks on the morphology of the Copepoda , 1947 .

[5]  R. Dennell.  II.—On the Feeding Mechanism of Apseudes talpa, and the Evolution of the Peracaridan Feeding Mechanisms , 1937, Transactions of the Royal Society of Edinburgh.

[6]  A. Lowndes.  The Swimming and Feeding of certain Calanoid Copepods. , 1935 .

[7]  C. Yonge.  FEEDING MECHANISMS IN THE INVERTEBRATES 1 , 1928 .

[8]  H. G. Cannon.  On the Feeding Mechanism of a Freshwater Ostracod, Pionocypris vidua (O. F. Müller). , 1926 .

[9]  W. Ziegelmayer.  Metamorphose und Wachstum der Cyclopidae , 1925 .

[10]  M. Hartog.  I. The Morphology of Cyclops and the Relations of the Copepoda. , 1888 .

[11]  R. Dennell.  VI.—The Feeding Mechanism of the Cumacean Crustacean Diastylis bradyi , 1934, Transactions of the Royal Society of Edinburgh.

[12]  R. Gurney.  British Fresh-Water Copepoda , 1933, Nature.

[13]  H. G. Cannon.  On the Feeding Mechanism of the Branchiopoda , 1932 .

[14]  S. Manton,et al.  IX.—On the Feeding Mechanism of the Syncarid Crustacea , 1929, Transactions of the Royal Society of Edinburgh.

[15]  S. Manton,et al.  X.—On the Feeding Mechanism of a Mysid Crustacean, Hemimysis Lamornæ , 1927, Transactions of the Royal Society of Edinburgh.

[16]  H. G. Cannon.  XV.—On the Feeding Mechanism of Nebalia Bipes , 1927, Transactions of the Royal Society of Edinburgh.