ABERRATION OF VANESSA URTJCvE, L. 85 



upset ; also these simplified markings in part stromjly suggest proformity 

 (atavism). 



It is well known, that, because temperature mostly acts indirectly, 

 very similar forms are obtained by frost — 2"^ C. to — 20° C. (Standfuss). 

 In jirticae aberrations and in io ab. belisaria, Obth., bred by either frost 

 or heat (pi. vii., figs. 10, 11), the wings are flooded with black (and blue- 

 white) ; in V. antiopa ab. hygiaea, Hdrch. (frost or heat) with yellow ; 

 in T'. atalanta ab. hleniensiewicsi, Schille (frost or heat) very beauti- 

 fully with red, blue and white. As protoform stages of development, 

 beginning with one cell, are quickly recapitulated by every 

 organism during development — passing from the simplest to more 

 and more complicated forms (Haeckel), and as this applies to the 

 whole, as also to the constituent parts (in this case to the markings 

 and colours of the developing-wing in the pupa), it follows that 

 " protoformity " Avill tend to appear and mix more or less with palae- 

 formity after a partial overthrow of the latter has taken place, because 

 "protoform memory" is potentially inherent in the organism, and 

 only needs to be carried on by active vitality. This vitality, defined 

 by the tendency to (actively) seek, and the capability to (spontaneously) 

 cause, new development in new forms directly the necessary favour- 

 able conditions are found or given, will, if only uninjured (and, 

 perhaps, stimulated), not only use up the primitive and palaeform 

 plasm-memory left, but will also overbalance the same by a + in 

 action, so that (grafted on protoformity and palseformity in a degree 

 corresponding with that in which fixed plasm-memory was sup- 

 pressed) progressive neoformity must infallibly result, and this neo- 

 formity will never be chaotic, but aim towards taking some definite 

 shape. If this aim be ocelli fonjiiti/, and if it be defined more clearly 

 in the case of V. urticae by colour and other detail as iofomiity, from 

 the closely-related ocelliform species, V. io, the above illustration will 

 be found to fit exactly the case of T'. urticae ab. iofonnis. According 

 to the theory of Standfuss {Handbuch d. Pal. Mac.-Lepido/it.), V. io 

 branched ott' from F. urticae under the continued influence of a raised 

 temperature acting on a great number of generations, and, if this were 

 so, it would seem that the " ioform " aim or tendency has always been 

 potentially inherent in 1^ urticae, and is, indeed, still there (as proved 

 by the ab. ioforwis), ready to crystallise into form when the conditions 

 are favourable. Naturally, in the youth of the species, soon after it 

 had finished laying its vital foundations as a butterfly, and had t/ieu 

 begun to develop embellishments in relation to light (colour) and 

 temperature, plasm-memory was not so strongly fixed as to-day ; 

 at, therefore, that period, leaps, both in colour and markings, 

 were probably relatively common [polymorphism; "form-throwing" 

 (Boelsche)] , thus offering " the material to be sorted by natural selec- 

 tion " (Standfuss), to be fully developed and to be fixed by repetition 

 into separate, relatively constant, species. 



1'. urticae ab. ioformis thus appears as the result of a potentially 

 inherent "ioform" tendency in I', urticae, brought into activity 

 through a partial suppression of fixed (palaeform) plasm-memory, 

 by the abnormal influence of the sun's rays and heat. As the direct 

 cause for the action of the potential physiological factor is here 

 again a physiological one, it becomes evident that ab. ioformis (or 

 other aberrations of the category) uii/iht appear " spontaneously " 



