2l8 ECOLOGY AND LIFE HISTORY OF THE COMMON FROG 



Data, biological large schemes, 177- 

 80 



Davidson and Andrewartha, 92, 181 



Davies, 183 



Deansley and Parkes, 42 



Death rate — 

 in frogs, 85, 86 

 in tadpoles, 207 



Delayed spawning, effect on eggs, 8 



Density-dependent factors in popula- 

 tion control, 80-3, 91-2 



Density of population of frogs, 84 



Dickerson, 5, 9, 14 



Difflugia, 46 



Digestion time in tadpoles, 44 



Digestive anatomy and physiology of 

 tadpoles, 49-53 



Dihydrol, 136 



Directiveness, 154 



DisLOglossus pictuSy 12 



Disease, 88 



Dismissal stimulus, 171 



Dissolved substances as food of tad- 

 poles, 22 



Distribution, i, 6-10 

 map, 2 



of spawn dates in S.E. England, 147-8 

 of spawn in ponds, 72-6 



Diver, 78 



Dodd, 51 



Dolk and Postma, 99 



Douglas, I, 5, 7-8 



Ducks as predators, 81, 87 



Egg-jelly — 



ecological properties, 14-15 



heat storage in, 3-6 



lack of nutritive properties, 16 



thromboplastins in, 10-14 

 Eggs- 

 delayed spawning, effect on, 8 



numbers of, 82 



thermal death points, i, 5 

 Elton, 196 

 Embyros — 



carbohydrate content, 16-17 



nitrogen content, 16, 18 

 Endocrinology and the breeding cycle, 



120-1 

 Enzymes — 



digestive, 45 



hatching, 19 



Equation, prediction of spawn date by, 



143 

 Euglena, 46, 159 

 Euryhelmis, 58 



External gills, function of, 21 

 Ezekiel, 183, 186, 192-3 



Fact and hypothesis, 70 

 Paris, 88, 142 

 Fatio, 89, 97 

 Feeding habits, 96 



tmderwater, 96-7 

 Fighting, 165-7 



drawing of, 167 

 Fischer-Sigwart, i, 88-9 

 Fish, 46 



Fisher, 150-1, 183 

 Food — 



chains, 47 



for adults not a limiting factor, 84 



of tadpoles, 44-9 

 Frazer, 11, 178, 186 

 Fretter, 49 



Gallien, 59, 64 



Gallinula chloropus, 16, 39, 87 



Gambusia, digestion in, 45 



Gayda, 22 



Geology — 



map, 76 



significance of the association of fiog 

 ponds with, 205-6 

 Giblett, 114 



GiU filters, action of, 52-3, 56 

 GiUs, external, function of, 21 

 Glasspoole, 142 

 Glyphoglossus molossus, 56 

 Goldacre, 49 



Graphs v. mathematical equations, 192 

 Gudernatsch and Hoffinan, 47 

 Gunn and Symmons, 180-1 



Halipegus eccentricus, 47 



Hatching enzymes, 19 



Hecht, 97 



Hellf and Stubblefield, 19 



Heron-Royer, 82, 97 



Hibernation, 97-9 



Hirudo medicinalis, 65 



Hormones and the breeding cycle, 



1 20-1 

 Huber, 165 



