76 THE entomologist's RECORD. 



shows that this sympathetic coloration is extended in some species to 

 the tips of the fore-wings beneath, in others, the whole of the under- 

 side of the fore-wing is sympathetically coloured, the area of the wing 

 thus coloured being coincident with the part visible in the attitude of 

 repose. The Professor then asks : — " Where are the formative laws 

 in such cases ? " 



In the sense that internal forces alone could give rise to this 

 sympathetic coloration, we would re-echo the Professor's question. We 

 do not believe that any formative laws originate the actual patterns from 

 within, in the way the question so distinctly suggests. We would 

 answer with the Professor that formative laws of this kind do not exist. 

 The scale determinants are subject to the same physiological laws as 

 those of other organs. They are guided in the course of their develop- 

 ment by various considerations, and there appears to be no doubt 

 that, whilst the general development of these is due to internal forces, 

 the exact peculiarities that they shall assume are determined by natural 

 selection. 



The learned Professor is most anxious to point out that when the 

 sympathetic coloration spreads over any portion of the underside of 

 the fore-wing, it is due to thedevelopment neither of new, nor of more, 

 scales than are present on the covered portions of the wing in the 

 same species. It is simply due to the wing being exposed, and he 

 asserts that " the scales are just as dense on the covered as on the 

 uncovered surface of the Aving, and, in many species, for example, 

 in Katai/rainnia, the scales of the covered surface are coloured most 

 brilliantly of all." 



We have now seen how internal variations and internal forces give rise 

 only to general results, that the detailed fashioning of these variations 

 into definite paths, so as to produce tints and patterns which shall be of 

 service to the species, is brought about by selection, and that selection 

 is guided in its action by utility, i.e., that although selection 

 chooses the particular variable factors for the purpose of building up 

 the required patterns, it selects only those which are useful for the 

 preservation of the species. 



The Tephrosia Tangle. 



By LOUIS 13. PROUT, F.E.S. 

 It is now fully two years since my interest was awakened in the 

 synonymic intricacies of the " Tephrosia question," through certain 

 passages which caught my eye in turning over the pages of Borkhausen, 

 the accredited sponsor of the name of />n<«J»Zrtrm {ride, Soiith's Si/n, 

 List, or Stgr's. Cat.) ; of which passages, more anon. I gradually got 

 together — at fitful intervals between my other studies — the more 

 important early Continental literature on the question, and had 

 recently decided to publish a note on Tephrosia crepnscularia and 

 T. biundularia (so-called) at an early date ; in fact, by a curious coinci- 

 dence, I had just returned from the British Museum, where I had been 

 supplementing my Continental notes with studies of our early British 

 authors, when, taking up the T'.M.M. for February, I was confronted 

 with Mr. Briggs' interesting note (p. 36) on the self-same British 

 authors. Mr. Barrett, in following the same question back amongst 

 the original nomenclators, quotes entirely from matter which I have 



