XIV CONTENTS. 



CHAPTER II. 



PAGE 



On the Artificial Hatching of Spawn 32 



Operations of the Thames Angling Preservation Society . ib. 



How to utilize a small Stream for Hatching Purposes . 34 



Plan of Hatching Box ib. 



How to distribute the Ova 38 



Plan for Greenhouse Apparatus 39 



Construction of Cistern 40 



Arrangement of Troughs 41 



Advisability of Filtration 43 



Various Plans for the Deposition of Ova 44 



Deposits and Confervse 45 



Putrefaction 46 



Use of certain Insects as Scavengers considered .... 47 

 Reception of various kinds of Ova from France and else- 

 where 49 



Temperature of Water considered 50 



Best way of carrying freshly-taken Ova 52 



Causes of Addling or Infertility of Ova 53 



Period of Incubation in Salmon 54 



„ „ „ Trout 55 



» „ Grayling 57 



How to detect the Fish's readiness to Spawn 58 



Method of expressing and preparing Spawn 59 



Another Method 62 



Apparatus for taking up Ova for Examination .... 64 



Progress of Incubation 65 



Period of Quickening 6Q 



Time of Hatching 67 



Appearance of newly-hatched Fish under the Microscope 68 



The Process of Hatching 69 



The Absorption of the Vesicle 71 



Accommodation for the Fry 72 



The Necessity of Rearing Ponds considered 73 



On feeding the Fry 75 



Varieties of Food 76 



CHAPTER III. 



On the Transport of Ova and Fry 76 



Method of Transport adopted at Huningue ib. 



On the Transport of Salmon to Australia 77 



