Descrizione

About the Book:-This book is a thorough study of butterflies in Sri Lanka and the author describes 233 different kinds. The author has often been asked what good the study of butterflies can do from an economic point of view. For answer he gives what he fears is a very incomplete list of butterflies, the larvae of which are known to feed on cultivated plants. The greatest difficulty in naming its forms lies in deciding whether they are species, sub-species or races, varieties, or aberrations. The real proof that geographical races are sub-species, or that any two different races of a species are sub-species, is not to be found in their segregation, or in the amount of their differences, but in the circumstance, that these differences have a permanence under any disturbance as of habitat, etc., that makes some approach to the permanence under such disturbance of a species. It is of course quite impossible to draw up any rule to fix at what stage in its development a variety becomes a race, or a race becomes a species. Butterflies can be studied anywhere in the Island, though only a few species could be expected in a district like Hatton where there is little jungle or waste land. The book also contains eight plates and diagrams to make it more interesting.

Edizione: 1924