Melanism and Melanochroism in 

 British Lepidoptera. 



By J. W. TUTT, F.E.S. 

 Strongly bound in Cloth. Price 5s. net. 



Some recent observations anent the phenomena of Melanism and Melanochroism in Lepi- 

 doptera, seem to suggest that little has been published on, and practically nothing Jcnown of, 

 the subject. Feiv new facts, however, have recently been brought to light, no new constructive 

 theories have been offered, and the superficial destructive criticism has been too hopelessly 

 weak to-be tvorth serious notice. 'The want of general information on the subject is painfully 

 evident in the case of many of the younger students, who have only too evidently neither 

 read nor digested the literature available on this absorbingly interesting subject. 



Contents. 



Melanism and Melanochroism in Lepidoptera — Localisation of melanic forms — 

 Leucochroism — Melanism in moist areas — Not found in high latitudes— Influence of 

 humidity — Review of the meteorological conditions of Europe — Of the great central 

 Alpine-Carpathian range— Of- the great Central Plain— Of the Mediterraneen area — 

 Distribution of melanic forms — Melanism in its geographical aspects — Peculiar meteoro- 

 logical conditions of Western Scotland — Outline of meteorological and climatic conditions 

 of British Isles — Influence of Gulf Stream — East wind — West of Ireland as a melanic 

 centre — The Hebrides, Orkneys, and Shetlands — Comparison of south England and 

 Highland forms of Lepidoptera — Melanism of the northern counties of England — 

 Comparison of distribution of melanic foi'ms with certain meteorological conditions — 

 Melanism in Western Scandinavia — Lancashire and Yorkshire melanism — Opinions of 

 Dobree, Cockerell, Buchanan-White, Cooke, etc. — Cooke's views of " natural selection " 

 criticised — Birchall and the influence of light— Chapman on darkening influence produced 

 by excessive moisture — Influence of natural selection in producing protected races — 

 Manufacturing areas — Smoke and humidity as melanism-producing factors — Influence of 

 wooded tracts on rainfall— On shutting out light — Melanism in Derbyshire— Sheldon's 

 suggestions as to growth of melanic forms in that county — Porritt on melanism of 

 Boarmia repandata- — Cooke on Tcphrosia crepuscularia, T. biundularia, and Amphidasys 

 betularia — White's criticisms — Melanism in trunk-frequenting species — Melanism at 

 Huddersfield and Sheftield — Edleston on Ampliidasys betularia — Dampness in woods as 

 afliecting production of dark forms — Chapman on Diurnea fagella — London smoke — 

 Deficiency of light as a possible factor — Eaces of Hypsipetes sordidata — Influence of wet 

 season of 1888 on lepidoptera — Connection between rainfall and variation in New Zealand 

 — Ground-resting species — Influence of natural selection — Variation of Gno.plios obscurata 

 and Boarmia repandata according to habits and habitat — Variation of Bryvphila perla, 

 B.muralis, etc. — Variation of marsh-frequenting lepidoptera — Eesting-habits of butterflies 

 — Criticism of superficial comparisons — Variation of Polia chi and Aplccta nebulosa — 

 Supposedinfluence of low temperature — Weismann's temperature experiments — Merrifield's 

 tempeiature experiments — Suggestions on some of the results— Climatic races in warm 

 countries — Walsingham's address on melanism — Criticism thereof — Peculiar views of 

 Dale on geology, meteorology, etc. — Cold as a factor of melanism— Heredity effects when 

 melanic races are started — Merrifield's further experiments on Ennomos autumnaria and 

 Selenia ilhistraria — Forcing pupae and results — Dimorphic seasonal forms in butterflies 

 and moths — Cockerell's views thereon — Larval and pupal development — Seasonal forms 

 in British species considered, e.i;., Pieris rapae, P. napi, Tephrosia bistortata (crepuscularia), 

 Selenia illustraria, S'. illunaria — Merrifield's views connecting heredity and the develop- 

 ment of seasonal dimorphism — Atavic (reversional) and progressive developmental forms 

 — Progressive development and partial melanism — The variation of Larentiid or "carpet 

 moths" — Eesting-habit of Larentiid moths— Melanism due to reversion — Tendency of 

 certain cripples and ill-nurtured lepidoptera to melanism — Disease as a factor in producing 

 melanism — Melanism versus suffusion — Walsingham's later views — Influence of light 

 discussed — Criticism of views that light influences melanic development — Decrease of 

 moisture producing paler races— Smith on results in New Zealand apparently produced 

 by difference of rainfall — Smith's criticism of Walsingham's remarks on melanism— The 

 theory outlined supported by observations on New Zealand lepidoptera — Phytopbagic 

 influences discussed — Plant foods — Size, variation, and food — Correlation of constitutional 

 difl'erences and the colour of animals— Views of Birchall and Wallace criticised— Influence 

 of surroundings on optic sense of adult insects — Criticism thereof — Various superficial 

 statements as to causes of melanism by Cooke, Prest, Robinson, etc., stated and criticised 

 — Larval stage influenced by various conditions that affect resultant imago— Physiological 

 factors bearing on melanism — Cockerell's theory as to combination influence of moisture 

 + some (unknown) melanism-producing factor — Chapman's theory illustrated diagram- 

 matically— Suitability of races to various climatic conditions — Suitable races acted on by 

 natural selection. 



Postal Order to— J. hERBERT TUTT, 22, Francemary Road, Brockley, S.E. 



