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COLLEGE ZOOLOGY 



Inedible Smyrna 

 fig (caprifig) 



Female wasp 

 becomes covered 

 with pollen of 

 mole flowers. 

 Fig wasps 

 develop in 

 gall flowers 

 of inedible fig 



Some female 

 wasps lay eggs 

 in flowers 

 of edible 

 fig and 

 pollinate 

 them 



Adult female 

 fig wasp 



Edible Smyrna fig 



Figure 448. The female fig insect shown is necessary to the production of the edible Smyrna 

 fig. Fig wasps do not develop in the edible fig even though eggs are laid in it. Both plant and 

 insect benefit from the relationship. 



the definitive host. The host which harbors 

 the larval stages of the parasite is the inter- 

 mediate host. A parasite that lives within 

 the body is an endoparasite, and a parasite 



Figure 449. Yucca moth female does not feed 

 on yucca plant, but lays eggs in ovary and deposits 

 pollen on the stigma. (Photo by Cornelia Clarke.) 



that lives on the outside of the body is an 

 ectoparasite. 



Ectoparasites attack many aquatic ani- 

 mals. A small copepod crustacean, the fish 

 louse [Argulus versicolor), is an ectoparasite 



especially on pike and pickerel. It is bril- 

 liantly colored with red, green, and orange, 

 and attaches itself to the host by the second 

 maxillae which are modified into sucking 

 disks. Leeches attack both aquatic and ter- 

 restrial animals. 



The ectoparasites of terrestrial animals 

 are principally arthropods. Human beings 

 are attacked by lice, ticks, and many others. 

 Probably most species of nonhuman ter- 

 restrial animals are inhabited by their own 

 peculiar species of ectoparasites, such as the 

 biting and sucking lice that infest poultry, 

 and the ticks that feed on cattle and on 

 many other animals. 



Endoparasites occur in both aquatic and 

 terrestrial animals and have been found in 

 every species that has been properly ex- 

 amined. Certain protozoans live as endo- 

 parasites inside the bodies of other proto- 

 zoans; others occur in species belonging to 

 every group in the animal kingdom. Trema- 

 todes, tapeworms, and roundworms are com- 

 mon endoparasites. Arthropods may also 

 live within animals; for example, the larvae 

 of the bot fly live as endoparasites in the 

 stomach of the horse. The larvae of mussels 

 are parasitic in the skin or gills of the fish. 

 Such endoparasites are all invertebrates. 



