92 THE entomologist's record. 



circumstance, revealing his single-mindedness and magnanimous 

 generosity, that he hands all the results over to Mr. Tutt^'= and myself 

 to be used as our own or in any way we choose. 



One of the most mteresfcing points about the genus Lujfia is that it 

 consists of two species, very much alike and yet vastly different. One 

 of them has the ordinary life-history common to most lepidoptera ; 

 the other is parthenogenetic, and only $ s are known. Of the 

 parthenogenetic species, L. fenlundtcUa, only $ s are known, and 

 though these are very like the ? s of the other species, L. lapiddla, 

 they are much smaller and are distinguishable structurally. This 

 does not, however, by any means exhaust this part of our subject ; on 

 the contrary, it opens up many curious questions which we are still far 

 from being in a position to settle, but which we may discuss, perhaps 

 with profit, in some of their aspects ; at any rate, it may be permitted 

 to bring together such facts as we have that may help us to understand 

 some of the questions, though they may not lead us far towards the 

 solutions. Many of these questions arise out of a main point for 

 consideration, viz : — Are we correct in talking of two species '? Are 

 there, perchance, several species (I do not mean still to be discovered, but 

 amongst those forms Ave already know) ? or, again. Is it possible that 

 there is only one species"? Our facts are, unfortunately, still too meagre 

 to enable us to come to any conclusions on these points, but they are 

 sufficient to make it desirable to raise the questions. 



Lajfui lapidrlla appears to have very definite characters and to vary 

 very little, whether the specimens come from Italy, Switzerland, France, 

 or the Channel Islands ; still we want longer series and from more 

 localities before we can be confident that this statement always holds 

 good, but, forthe present, that seems to be the case. L. fcycliaidtdla, how- 

 ever, is very variable in some directions. Typical /.. fnrkatdtdla is much 

 smaller than />. Lapiddla, has fewer antennal joints, and has fewer 

 tarsal joints; nevertheless, there are great differences in the formula 

 of the tarsal joints in specimens from different localities. There are 

 also great differences in the forms of the scales, which so characteristi- 

 cally clothe the segments in both species. Being parthenogenetic, 

 there can be no crossing, and consequently it is easy to see that a 

 separate race can hardly avoid resulting in each locality if there are 

 any circumstances likely to cause variation. Whilst, then, we may 

 assume tliat all these races have a common ancestry, it is purely a 

 matter for individual consideration to decide how much difference 

 between two races shall be sufficient to constitute it a distinct species. 

 There is, however, another series of facts that cuts in quite the opposite 

 direction. I found, two years ago, at Bignasco, in the Val Maggia, 

 cases of y>.,/r/y7/rt»^ir//rt in some abundance. The moths reared from 

 these cases are distinctly L.fcrcJianltdla in size and structure. Those 

 I sent to Mr. Bacot, however, were definitely observed by him to 

 " call," i.e., to await in expectation of the male, and refused to lay eggs, 

 whilst typical /.. fcrc/iaidtdla lays her eggs as soon as she emerges. I 

 am sorry to say I did not observe so closely, but it is certain that no 

 young larvte appeared either amongst Mr. Bacot's or my specimens, whilst 

 with typical L. ferchaidtdla the boxes would have swarmed with them. 



* I should like to identify myself most absolutely with this sympathetic and 

 just remark of Dr. Chapman. Such value as there may be in Ilritish I.cpidupteru 

 is due quite as much to Mr. Bacot, Dr. Chapman and Mr. Prout as to myself. — Ed. 



