CHAPTER 11. 



SUMMER DELIGHTS — MEDUSA-HUNTING — NOCTILUCA AND THE PHOSPHORES- 

 CENCE OF THE SEA — THE CTDIPPE — VIVISECTIONS — DO THE LOWER ANI- 

 MALS FEEL PAIN ? — CHANCE- WEED — A NEW POLYPE — A NEW POLYZOON — 

 VITALITY OF MOLLUSCS— VISION OP THE MOLLUSCS — ARE IMAGES FORMED 

 ON THE RETINA? — DESCRIPTION OP THE RETINA IN VERTEBRATES AND 

 INVERTEBRATES — NEW THEORY OP VISION — TACTILE SENSATIONS AND 

 NERVE FILAMENTS — CAN THE MOLLUSCS HEAR ? — THE SENSES OF ANI- 

 MALS NOT SUPERIOR TO THOSE OP MAN — THE OCEAN-CURRENTS CAUSED 

 BY MOLLUSCS. 



Theee are perspiring individuals avIio love not summer in 

 its sultry splendour. With bubbles on their upper lips, they 

 languidly declare the heat is insupportable. It is not often 

 that our English summers swelter with intolerable heat ; 

 and when the blazing sun does pour fierce radiance on the 

 land, who have true right to murmur ? Only those unhappy 

 victims of civilisation doomed to move along stifling streets, 

 with souls yearning for the far-off woodlands and the breezy 

 sea-boards ; or those victims of agricultural necessities who 

 toil amid the shadeless corn. Nobody else. The heat is hot, 

 undoubtedly ; but it is beneficent. Nature ripens ; life cul- 

 minates ; let no one murmur. I am in a permanent vapour- 

 bath while writing this, yet the temporary discomfort cannot 

 quell my invincible delight in summer : it only gives a more 

 exquisite sense of the evening coolness, and the breezy shade. 

 To walk out under this August sun demands a touch of 



