202 



Index 



migrate to sea, 10 



on land, 16 



optimum humidity, 85 



origin, 31 



salinities endured, 45, 72 



sense organs, 136 

 insular animals, 46 

 integument, 96 

 invertebrates, blood salinity, 8 



osmotic swelling, 78 

 iodine, in sea water, 123 

 iron, 6 



in sea water, 42 

 islands, as routes, 45 

 isohalin animals, 76 

 isopods, in Elbe estuary, 28 



in salt marshes, 33 



on islands, 45 



parasitic on crabs, 67 

 isopods (Continued) 



reproduction, 134 



salt tolerance, 77 



water requirement, 86 

 isotonic animals, 76 



Jdera marina, 30 



jellyfish, 79 



jerboa, does not drink, 87 



Kaiser Wilhelm Canal, 44 

 katydids, activity, 90 

 kidneys, 129 



control of body fluids, 99 



functions, 130 

 killifish, 75 

 king crabs (see also Limulus) 



adaptability, 41 



dilution toleration, 71 



in estuaries, 26 

 in Ganges delta, 27 

 Krakatao Island, 46 



labyrinthine organs, 105 



lactic acid, secreted, 120 



Lake Lanao, P. I., 50 



Lake Tanganyika, fauna, 43 



land, compared with fresh water, 13 



compared with ocean, 13 



habitats, 92 



elevation, 46 

 Laonice, 41 

 larvae, free-swimming, 22 



veliger, 134 

 larval stages, 8 

 (leeches, desiccation resistance, 87 

 ^— fasting, 92 



on land, 93 



spreading parasites, 50 

 Lepidosiren, 60 

 Lepisosteus, respiration, 104 

 Leuresthes tenuis, 66 

 light, 6, 89, 91 



definition, 89 



in depths, 9 



in zonation, 55 



necessary to plants, 56 

 Ligia baiidiniana, reproduction, 134 



salt tolerance, 77 



L. exotica, water requirement, 

 86 

 Ligyda Oceania, 30 

 lime, in sea water, 42 



in streams, 59 

 limnaeids (see also gastropods) 



damp-air-breathers, 96 



in fresh water, 15 



