194 



NATURE 



[June 30, 1898 



and in the centre of the spiral there is a round spot of 

 the same colour. The black line obviously is meant to 

 serve as a setting of the yellow spiral," 



but it is somewhat misplaced in the design, being shifted, 

 together with the central spot, towards the base of the 

 wing. 



" We have, consequently, three colours stencilled on 

 the glassy wings: first green (Fig. "job), then lemon- 

 yellow {c\ and, to complete the picture, a black body 

 colour ; the latter is somewhat misfitted, as it may also 

 be at times in our coloured prints." 



All the specimens examined were found to exhibit the 

 same displacement of the black band, so that it is not 

 " a mere chance occurrence in an individual." The 

 author reaches the remarkable conclusion — " The species 

 was ornamented once for all, and just as it emerged from 

 this operation, so has it been transmitted by inheritance." 

 Stencil painting also occurs in Lepidoptera, although it 

 requires "a little good will" to find it. Indeed Brunner 

 is inclined to look upon this as the primitive coloration, 

 which has been in the Lepidoptera "frequently effaced 

 by selection and by simply going to the bad." 



The transparent patches which occur on the wings 

 especially of Orthoptera and Lepidoptera are classed 

 under (lo) Erosion. 



These ten groups of marks are followed by general 

 Sections dealing with the alterations which occur in 

 pattern as it is traced through a series of allied forms. 

 In Section (ii) Changes of Patterti, it is pointed out that 

 unlike the Pseudocreodotra, described above, the outlines 

 of spots and stripes and even their position are variable 

 in Lepidoptera. 



The author therefore compares 



" the first method of coloration with colour printing, and 

 the latter with hand painting ; thus indicating the fact 

 that on one hand we meet with undeviating similarity, 

 and on the other with a certain freedom." 



The methods by which the changes are efifected are 

 then considered in (12) Enlargement and Diviitmtion of 

 Spots and Bands, (13) Dislocation, the change in position 

 which corresponding marking may undergo in allied 

 species, principally illustrated from the Hesperidce. (14) 

 Diminution of Patterns, in which a " pattern remains 

 unchanged and only diminishes in size." The fascination 

 for metaphor whith possesses the author leads him to say 

 concerning diminution (as opposed to " the simple 

 breaking down of a design "), 



"We have a process before us, which is carried out 

 physically when a magic lantern picture is diminished on 

 the screen by manipulating the lenses." 



The title of Section (15) is Changes of Colour due to 

 Adaptation. Although the choice of these words seems 

 to imply the recognition of natural selection, such an 

 explanation is by no means congenial to the author. 

 After alluding to his previous description of a Locustid 

 from the Soudan which resembles an ant, the shape of the 

 latter being indicated in black pigment on the body of the 

 former of which all other parts are coloured with a pale 

 tint, he inquires " is this imitation an accidental freak of 

 nature ? " Indeed throughout this section Brunner seems 

 to doubt his own explanations. He gives numerous 

 instances of insects living on plants " in which the leaves 

 NO. 1496, VOL. 58] 



of the habitat or parts of them are doubtlessly imitated " ,- 

 but follows the list, which is illustrated by eight figures, 

 with the paragraph — 



"With the aid of the imagination, one may recognise 

 the most various figures in the an-angements of spots and 

 ocelli, and if, perchance, these can be referred in any way 

 to protective resemblance, your case of mimicry is 

 established." 



Apart from the fact that such a description is a cari- 

 cature, exception must also be taken to the inconvenient 

 confusion between protective resemblance and mimicry, 

 two principles which, although bearing a dose relationship 

 to each other, are better kept separate. 



(16) Staining of Contiguous Parts. — This Section con- 

 tains the somewhat crude and entirely unsupported 

 assertion that when an intensely coloured part of the 

 body is of the same tint as other parts which are in 

 contact with it, the latter have been stained by the 

 former. Careful microscopic investigation at the time 

 during which the pigments are developed would settle 

 the matter, and without it no such assertion can be 

 justified. 



(19) Fading in Covered Parts. — In many instances the 

 parts of wings which are covered in the position of rest 

 are of a different tint from the exposed portions. From 

 this well-known fact, and without the remotest attempt 

 at proof, the author observes 



" these facts convey the impression that the brighter 

 colours are produced by daylight. If one exposes to the 

 action of the sun and of the air several sheets of white 

 paper of different sizes lying one upon the other, then, 

 in a short time, the silhouette of the smaller pieces will 

 stand out on the larger either in lighter or in darker 

 tints. It is probable that the phenomena observed in 

 Blattodea and Phasmodea belong to this category of 

 light effects." 



The author's rhethod of dealing with natural selec- 

 tionists may be fairly used against himself. If, perchance^ 

 it is possible to institute a crude comparison between the 

 colour effects produced by physico-chemical forces upon 

 dead matter, and the arrangement of tints in a highly 

 organised being, you have probably established a valuable 

 " law " which you can then place before the world, with- 

 out troubling to inquire whether you have been misled 

 by a resemblance which is purely superficial. 



{i2>) Colourittg in Relation to Position. — In this Section 

 the patterns which pass over the body irrespective of its 

 parts, and produce a "homogeneous" effect, are distin- 

 guished as holotypic from those correlative markings 

 which are similar upon homologous parts, as in the 

 repetition of ocelli upon the corresponding areas of fore 

 and hind wing, &c. Numerous interesting and beautiful 

 illustrations are given. It is common for the same insect 

 to possess more than one holotypic pattern having refer- 

 ence to more than one position. This at least is the way 

 in which a follower of natural selection, or indeed a 

 Lamarckian, would express the facts, and he would 

 then attempt to ascertain the meaning of the patterns in 

 relation to the positions. Brunner expresses them very 

 differently and in a manner which is significant of his 

 views of creation. With him the position represents the 

 attitude of the insect when the pattern originally fel) 

 upon it. Such a view is expressed again and again, the 

 best example being contained in the next and last 



