228 STRANGE D IV ELLIN GS. 



CHAPTER XX. 



SUB-AQUATIC NESTS. 



INVERTEBRATES. 



A Pool and its wonders — The Water Spider — Its sub-iiqiiatic nest — Convey- 

 ance of air to the nest — The diving-bell anticipated — Character of the air in 

 the nest — Mr, Bell's experiment upon the Spider — Life of the Water Spider— 

 The Hydracmna— The Caddis Flies and their characteristics— Sub-aquatic 

 homes of tlie Larva— Singular varieties of form and material — Life of a 

 Caddis — Description of nests in my own collection — Fixed cases, and modifi- 

 cation of Larva — Singular materials for nest-building — Different species of 

 Sabella— The Silkworm Amphitrite —The Terebell^ and their sub- 

 marine houses— The Caddis Shrimp — Remarkable analogy. 



When I was a very little boy, I was accustomed to spend much 

 time on the banks of the Cherwell, and used to amuse myself 

 by watching the various inhabitants of the water. Animal life 

 is very abundant in that pleasant little river, and there was one 

 favourite nook where a branch of a weeping- willow projected 

 horizontally, and afforded a seat over the dark deep pool, one 

 side of which was abrupt and the other sloping. 



Here the merry gyrini ran their ceaseless rounds, and the 

 water-boatmen rowed themselves in fitful jerks, or lay resting in 

 a contemplative manner on their oars. Now and then an un- 

 lucky insect would fall from the tree into the water, and then 

 uprose from the dark depth a pair of dull eyes and a gaping 

 mouth, and then, with a glitter as of polished silver, the dace 

 would disappear with its prey. In the shelving part of the pool 

 the caddis-worms moved slowly along, while the great dyticus 

 beetle would rise at intervals to the surface, jerk the end of his 

 tail into the air, and then dive below to the muddy bottom. 

 This spot was much favoured by the nursemaid, for she had no 

 trouble in watching me, as long as I could sit on the branch and 



