30 



necessarily taking up the time of this Meeting, and I should not have recurred 

 to the subject but for the number of young entomologists who now attend our 

 Meetings, on some of whom the idea of gradual developments from one species to 

 another might have most injurious effects, were it not briefly, yet eflfectually, 

 exploded." 



Mr. Westvvood considered it would require far greater research than had yet been 

 made, and far more argument than the few lines Mr. Stainton had just read, to dis- 

 prove the theory he bad advanced at the last Meeting, although Mr. Stainton was 

 pleased to imagine he had " effectually exploded " the idea of gradual developments, 

 yet he (Mr. Westvvood) still maintained that many of the supposed new species of 

 Micro-Lepidoptera lately established might be merely modifications of other species 

 dependent on diversity of food or otlier circumstances with which we are not 

 acquainted. That many species of animals, including insects, underwent modifica- 

 tions and became, so to speak, geographical or structural sub-species was well 

 established, as might be seen in Mr. WoUaston's work on " Species," since the publi- 

 cation of which a great change had taken place in the minds, especially of German 

 naturalists, as to the specific rank of many of the supposed species of Carabideous in- 

 sects, which were now sunk into local sub-species. It was not sufficient to say that 

 larvae which had fed on the oak, would die rather than feed on any other tree, because 

 the experiment was tried with an individual which had already become quercivorous. 

 Many of the best butanisls had also adopted the theory of local sub-species; it was 

 quite necessary to register these permanent or even transitory sub-species, but far 

 more philosophical to endeavour to discover the centre, so to speak, from which they 

 radiated. 



Mr. Douglas remarked that in some of the species most closely allied, as, for in- 

 stance, Cemiostouiii Spartifoliella and Ijaburnella, it was not merely that they fed on 

 different plants, but the habit of the larvte was totally different, and it would 

 be a preposterous doctrine to maintain that the difference of the habit was the cause 

 of the modification of the species, and not rather that the habit differed because 

 the species were different. 



Mr. Dunning said he was no advocate for the notion of species gradually 

 changing from one form to another. 



Mr. Stainton observed that Mr. Westwood's remarks went fully the length of 

 maintaining the development theory, and in further illustration of the difference of 

 habits, showing closely allied species to be distinct, he exhibited larvae of M. Mil- 

 liere's new Coleophora Lugduiiiella, feeding on Vicia Cracca, and larvae of C. Vibi- 

 cella, on Genista tinctoria ; the former larva having an ample silken cloak thrown 

 over its black case, and the latter being entirely without the cloak ; the former larva 

 eating the leaves through into holes, and the latter blotching the leaves in the usual 

 Coleophoric fashion. 



Mr. Vardou called the attention of the Meeting to the lamentable slate of the 

 fruit trees in Worcestershire : a few weeks ago they promised one of the finest crops 

 ever seen, which had since been totally destroyed by multitudes of caterpillars, some 

 of which he laid before the Meeting. His own orchards were planted with currant 

 and gooseberry bushes under the fruit trees, and the caterpillars after defoliating the 

 latter, had descended to the former: he would feel much indebted to the members 

 present for any suggestions calculated to remedy or mitigate this serious evil: the 

 crop on at least 1000 acres being totally destroyed. 



