88 THE entomologist's record. 



the general facies of the specimens captured in the Alps of Dauphin6 

 the Tyrol, Kent or Yorkshire. 



The essential difficulties of the group, so far as our British species 

 are concerned, lie in the study of Z. trifolil and Z. tilipcndular. 

 Before considering these, however, in detail, it may be well to 

 observe that (1) Z. hmicerae has been crossed with Z. jilipendulac, and 

 the hybrid progeny, although exceedingly large, failed to produce 

 fertile eggs. Mr. Fletcher, however, does not consider that this 

 proves the hybrids to be infertile inter sc, although he was unsuccessful 

 with this particular brood. (2) Z. hmicerae has been crossed with 

 Z. frifolii, and the hybrid progeny have proved fertile inter se to the 

 fourth generation. (3) Z. ochsenheiirwri from the Alps (Courmayeur), 

 and Z. jiUpcndulae (Sussex) have been crossed, and the hybrid progeny 

 produced fertile ova. 



Mr. T. H. Briggs was, we believe, the first entomologist to point 

 out that we had in Britain three very distinct five-spotted Burnet 

 moths (excluding Z. exulaux and Z. mcliloti) Avith distinct life-cycles. 

 (1) The early (and small) Z. trifoUi, found usually in pastures and 

 meadows in May and early June (often with Prucris statices). (2) The 

 well-known and well-defined Z. hmicerae occurring in June and early 

 July. (3) The late (and large) Z. trifolii-viajor found in marshes in 

 July and early August. Very few entomologists appear to know all 

 three of these in a state of nature. Exact and comparative life- 

 histories of the first ftrifoUi) and last (trifoUi-inajor) are very much 

 needed. 



Another difficulty has to be explained, riz., the nature of the 

 relationship existing between the two forms of six-spotted Burnet 

 moths that exist in Britain. These are Zi/i/aena hijipocrejii'li.s, St., 

 and Z. fiUpendnhit', Linn. The former occurs with (or just a few days 

 later than) Z. trijhUi, and in the same or similar localities to those 

 frequented by this sj^ecies. Having six spots, the specimens are 

 usually referred to as Z. fdipendnhic, although those who have recorded 

 them as such have usually stated that the true ^./77<^j('»^//<Zflf has been, 

 even in neighbouring localities, in the larval state, whilst these 

 aberrant six-spotted specimens were flying. These six-spotted speci- 

 mens have usually the marginal band of the hmd-wings broader, and 

 the sixth (outside) spot of the fore-wings less well-developed, than in 

 Z.fdipendnUie; and Boden, who observed in a series of Continental 

 Z. oc/isenJiei)neri (for sale in Stevens' rooms), the ill-developed sixth 

 spot, referred our May and June six-spotted specimens to Z. orJi.sen/iei- 

 ii\eri, and the name has been erroneously applied to them ever since. 

 "Wood figures a yellow aberration of this form under Stephens' name. 

 This difiiculty has been complicated by the fact that we have a 

 common aberration among true Z. jilipendidac, parallel, so far as the 

 peculiarity of spotting in these early Z. hipporrepidis and Z. ochxenhei- 

 iiirri is concerned, and hence we find, in collections, a mixture of 

 Z. Iiippocrepidia and the aberrations of true Z. jilipendulae which 

 assume a similar form. 



The difficulties of our British species do not seem to extend to the 

 late (July and August) Z. trifoUi, which, in its marshy haunts, is 

 rarely overrun by the other species. The only difficulty that I have 

 observed is one with regard to "Weston's specimens, referred to by 

 Briggs, and quoted later on in this paper. 



( To he cun tinned.) 



