1922] on Biological Studies in Madeira 575 



known nothing of all this but for the accident of the telegraph cable 

 •crossing the district of this submarine commotion. Knowing all this, 

 I was intensely interested in hearing, two years ago, at the British 

 Association, Professor Herdman's account of the destruction of a 

 fishery in the sub-tropical waters of the United States. The narrative, 

 full of interest, runs thus : — 



The capture of a solitary fish, a new species of the Tile fishes 

 named Lopholatilus Chamseleonticeps, led to the discovery by the local 

 authorities of a well-stocked fishery which for two years substantially 

 augmented the fish-market supplies of a long stretch of the American 

 coast. Then, in Professor Herdman's words — something happened, 

 and the sea surface for hundreds of square miles was strewn with 

 dead Tile fish in amazing quantities. The authorities again sent to 

 investigate the ground, but not a single fish was taken, and it was 

 found moreover that the destruction had extended even to the 

 invertebrate inhabitants of the same district. An attempt to account 

 for the catastrophe by a suggestion of a sudden change of tempera- 

 ture due to a deflection of sea currents seemed to me unsatisfactory, 

 and in the light of what happened at Madeira it seems more highly 

 probable that certain fissures were volcanically opened, and that the 

 water was poisoned by the issue of noxious vapours without any 

 surface evidence of what happened but floating myriads of dead fish. 



I can go no further in this branch of natural history, though I 

 could fascinate you with a sketch of many anatomical details, and 

 especially of heart structure and function. 



You must go to Madeira for any full and comprehensive appre- 

 ciation of sub-tropical ichthyology. You can take part, if you will, 

 far away in the open sea, in the exciting capture of our huge, 

 voracious tunny fish ; you can study inshore the shoals of grey 

 mullet, shapely and silvery, in their search for fresh water ; you can 

 see our full-tinted red mullet, brought out of shallow water in 

 unbaited basket traps into which they have aimlessly wandered : 

 you can see the deep blue water tinted with the reflected purple of 

 inviting rock fish ; or you can study in our markets the daily display 

 in vivid colouring of Sebastes, Scorpoena, Beryx and Polymixia, inter- 

 spersed with many a turtle, octopus, and strange crustaceans in 

 surprising confusion. And all this will be doubly interesting if it 

 evokes in you a desire to study and increase knowledge ; for it is 

 clearly our duty to continue the work of investigation and classifica- 

 tion which hitherto has been mainly due to our own countrymen. 

 And surely a sense of responsibility attaches to us when we are 

 reputed by the races of the South to be the custodians and exponents 

 of science in general. We are lucky, indeed, if we can justify one- 

 tenth part of the knowledge attributed to us. 



But apart from any such consideration there is a satisfaction and 

 charm in the pursuit of any branch of natural science for its own 

 sake, which will grow and expand with experience. But every man 



