THE CANADIAN ENTOMOLOGIST. 21 



ADDITIONS TO THE LIST OF MANITOBAN LEPIDOPTERA. 



BY E. FIRMSTONE HEATH^ CARTWRIGHT, MAN. 



A good many fresh species and some few new to science have been 

 taken in Manitoba since the pubHcation of my Ust in 1904 — additional to 

 that by Mr. A. W. Hanham, then residing in Winnipeg, which appeared 

 in this magazine a few years previously. Before giving my record I may 

 make some remarks upon the appearance, disappearance and apparent 

 migration of some species, which, I trust, will prove interesting. 



When first I began to collect here, about 25 years ago, Pieris 

 protodice, Bd. and Lee, was the only white butterfly and was abundant. 

 Then a few stragglers of P. rupee, Linn., appeared, and the number of 

 protodice became gradually less and less ; now it has entirely disappeared, 

 and we have to wage war with rapce in order to grow a few members of 

 the cabbage family in our gardens. Last year this species made a clean 

 sweep where pyrethrum powder was not used. In my own garden it fell 

 back upon a bed of mignonette, greatly to its detriment. In England 

 rapce, with its relative brassicce, is kept in check by a small ichneumon 

 fly j here it seems to be unmolested, and it seems desirable to import the 

 parasite. 



Colias casonia, Stoll. , appeared here some years ago and in some 

 numbers. I caught two and saw many more flitting over growing grain, 

 where they could not be followed; none have been seen since. 



Vanessa Califorjiica, Bdv., has appeared twice at dates several years 

 apart. Pyrameis Hunt era, YdiO'c.^ is also of very urjcertain occurrence. 



Some of the Theclas used to be plentiful — now they have all 

 disappeared. Likewise many of the Pamphilas that I used to take are 

 no longer to be found. 



Argyn?iis Edwardsit, Reak., a green-winged species, appeared in 

 numbers some years ago. I took a couple of dozen, and could have 

 taken more. It disappeared as suddenly as it came, and not one was 

 seen during the following season. 



With both butterflies and moths — especially the latter — there seems 

 to be a gradual and constant migration from the south west, northv/ards as 

 far as Manitoba, but very little movement from due east to the westward, 

 or vice versa. The cool, high land north of Lake Superior seems to form 

 a barrier to migration from Ontario, and the bare, treeless plains to our 

 west are an obstacle to Albertan species. Still, some forms new to 

 science occasionally appear, and it is a puzzle to know whence they came. 

 In the south-eastern part of this Province there is much roughly-wooded 



January. ^1908 



