ANTHROCERA. 425 



area of the wing as a single red blotch. The form known as A. 

 exulans ab. pulchra is an almost parallel form to A. purpuralis ab. 

 polygalae, but yet shows some traces of the yellow nervures that separate 

 the three blotches ; A. exulans ab. striata tends in the direction of joining 

 3 and 5 or 2 and 4 by fine red lines. In A. lonicerae, there is a tendency 

 for 1 to form a long wedge-shaped spot along the basal half of the 

 costa, then for 2 and 4 to run together and make a somewhat straight 

 line parallel with the inner margin, as in A. purpuralis. Here the 

 similarity seems to end, for 4 now joins with 5, and then falls back to 

 include 3, so that at length 2, 3, 4 and 5 form a large roughly wedge- 

 shaped spot with the apex of the wedge at 2, and its base extending 

 along the outer edge of 5 to 4, and roughly parallel with the outer 

 margin of the wing. This also seems to be the line taken by A.filipen- 

 dulae, but in this, after 2 and 4 have become united, 3 will join into 

 the blotch at 4, and also with the united 5+6, leaving a space 

 between 4 and 5 + 6. If now we examine A. trifulii, we observe that 

 the commonest form of blotching is that by which 1 + 2, 3 + 4, and 

 5 become three separate spots. Then we observe that 1 + 2 is joined 

 to 3 + 4 by a narrow line = ab. basalis, Selys, and in others that 



3 + 4 is joined to 5 in the same manner = ab. glycirrhizae, Hb. 

 The next step is 1 + 2 joined to 3 + 4 by a red line, and 3 + 4 joined 

 to 5 by another red line, so that we have two terminal and a central 

 blotch, borne, as it were, on a central bar = ab. minoides, Selys = 

 confluens, Stdgr. The growth of this bar continues, in some instances, 

 until the whole central area is practically filled up. Such an aberra- 

 tion is figured by Christy {Entom., vol. xxix., p. 341). 



With regard to this development, Speyer (Stett. Ent. Zeit., xxxviii., 

 p. 40 et seq.) notices that the farthest removal from the typical spotting 

 occurs in those species which have lost the pairs of spots as such, and 

 have, in their place, three longitudinal streaks, of which two spring 

 from the base of the wing, whilst the third occupies the discoidal cell, 

 and pushes its narrow basal half between the other two. This is . 

 caused by spot 1 lengthening towards the apex to a point, whilst 2 

 joins with 4 and 3 with 5, whilst 6, if present, is united to 5, and 

 forms the broad base of the central streak, extending over ^branches 1 

 and 2 of the median vein. This extension is well shown in A. purpuralis 

 (viinos) and A. erythrus, whilst in those species in which the three 

 streaks have been developed from 5 (and not 6) spots, as in A. scabiosae 

 and A. brizae, this widening is wanting. Speyer further remarks that 

 the development of the streaks from spots can be readily traced in 

 A. achilleae and A. cynarae, whilst the retrogression of the streaks 

 through partial loss of the red coloration may frequently be traced in 

 A. scabiosae, and A. purpuralis. 



Speyer, however, discovered a form of A. trifolii, which he named 

 trivittata, from the fact that its markings were characteristically like, 

 and similarly formed to, those of A. purpuralis, i.e., spot 1 forms a 

 narrow streak reaching to the middle of the costa ; the middle streak, 

 formed by the union of 5 to 3, is divided from the first by the black sub- 

 costal nervure, is rounded at the end, and of equal thickness until half- 

 way to the base, when it narrows to a sharp point between the stems 

 of the subcostal and median nervures ; the lowest streak is formed by 



4 joining 2, and is broadest at the end situated in the middle of the 

 wing. This belongs to the small-winged form of this variable species. 



