86 THE entomologist's record. 



Leaving this question of melanism, Mr. Mansbridge has, in his farther 

 statdnent, given much food for thought. He considers "all cases 

 of change troin yellow to red, or red to yellow, and similar changes 

 where the break is sudden as mutations," i.e., that those variations 

 that are most effective in their appeal to the human eye are "muta- 

 tions," and those that are less so are " Darwinian variat ons;," and 

 herein the nakedness and poverty of argument, and want of appreciation 

 of the facts lie bare. Is it at all necessary to assume that the d ilerence 

 between a yellow hindwing and a red hindwing, in Arctia caia, is greater, 

 biologically, than between an ord'nary typical Acidalia viriinlaiia, and 

 its Kiifftiml London form, or that a yellow-spotted aberration of 

 Antluocera trifolii has a greater biological significance than say the 

 dift'erence in the colour of 3' Spilosnuia incndira, compared with that 

 of the 5 ? Do- the eggs from a yellow-spotted $ of AnfJuorera trifoUiy 

 or of a yellow hindwinged Arctia caia, or a suffused Abraxas si/lvata 

 (ulriwta) of necessity produce progeny with " yellow spots," '• yellow 

 hindwings" or "suffused" wings respectively? Do they produce 

 necessarily their own "leap"-i<ind to perpetuate the marvellous 

 biological wonder ? We know well they do not. 



We would like, without impertinence, to again refer Mr. Mansbridge, 

 not only to our remarks {Brit. Nuctitae, etc., ii.,pp. ix et seq.) and the sug- 

 gestions that arise from a study of the advance of ochreous and yellow 

 forms to red or brown, in (Julias ediisa, (Toneptertj.v cleojiatia, llnmia 

 cratacffata, Arctia caia, Nenicojihila jilanta/jiiiis, A. rillica, Cocnimtjinpha 

 pa)ii/)liiluK, C. davus, Kpinju'liele tillmnits, (Jullimorplia liera, Satyrim 

 semele, and many other species, but we would like to call his attention 

 to the retrogressive condition arising, possibly, in an entirely different 

 direction in Calliinorpha donriniila, Aiithrocera Jilipendidae, A. trifolii, 

 A. lonicerae, A. purj>tiralis, A. acliilleae, Catocala niipta, Casmotrich* 

 patatoria, Pacln/r/astria trifulii, Fhitricha qiierci folia, and a whole host 

 of Noctuids and Geometrids. We would ask for a fair criticism of the 

 facts known and theories advanced; these haphazard statements which 

 mean nothing, and lead nowhere, are getting wearisome. 



Our older and well-informed lepidopterists will doubtless say, why 

 treat so small a matter so seriously. My answer is that, if on)}'' our 

 older and well-informed lepidopterists were readers of the entomological 

 magazines, it would indeed be unnecessary, but year by year new and 

 young members come in, who, of necessity, are ignorant of the work 

 that has been done, and yet are anxious to learn. There is a time 

 when oft-repeated errors, erroneous opinions and ill-judged statements, 

 sink as facts into the minds of those who know no better, and one 

 learns very early in the educational field, that it is more difficult to 

 eradicate an error, than it would have been at first to teach the truth. 

 Hence it becomes necessary, now and again, to ask those who, in their 

 turn, would profess to teach, to themselves make sure of their ground, 

 to remember that assertion does not necessarily include accuracy either 

 in fact or argument, that what the best know is but a trifle, and 

 that to teach others even a part of that trifle, one must make sure of 

 one's own facts first. It appears to be unfortunate that the few 

 reprints that were at the time made of the essays on " The genetic 

 sequence in Insect Colours," and " Secondary Sexual Characters in 

 Lepidoptera," and which appeared as introductory chapters to vols, ii 

 and iii of 2'he Ihitix/i yoctiiac and their Tar/t^^/Vs, were so soon dispersed. 



