THE SPREAD OF A BUTTERFLY IN A NEW REGION. 1177 



Anne's on the soutli shore of the St. Lawrence seventy miles clown the 

 river "where a collector of Lepidoptera resided." From what we know 

 of tiie rapidity with which a siiijrle pair may propajjate without hindrance 

 from [)arasitcs, we may coiicliule almost with certainty that it was intro- 

 duced in the early part of 1860 or at the earliest at the very close of 1859. 

 Owing, apparently, to Mr. Bowles' paper, published in the Canadian 

 Naturalist in 18(54, in which he fixes the period of its introduction to 

 Queliec "at about seven or eight years ago," it has been generally spoken 

 of as introduced "in 1856 or 1857." But Mr. Bowles has allowed more 

 time tlian is necessary, and records do not go back of 18(50. 



Following the report of Mr. Couper of its distribution in 18(5,5, we have 

 at first but scanty information concerning its spread in Canada. Captain 

 Gamble Geddes of Toronto states that he first took it "about 1864, about 

 ninety miles below Quebec ; when I brought it back and showed it to Pro- 

 fessor Fowler, then connected with tlie Natural History Society of Mon- 

 treal, he assured me that it was quite the first that had been taken." This 

 fixes the date of capture as before the publication (in Montreal) of Mr, 

 Bowles' paper and indicates that in 1864, the insect had spread to Murray 

 Bay, on the north shore of the St. Lawrence. 



In 1866 begins our first considerable knowledge of the spread of the 

 butterfly, as it has reached more populous districts. Mr. William Saun- . 

 ders, on an excursion to tlic Sagucnay, found it at Cacouna opposite and 

 a little above the mouth of the river and at Ha Ha Bay at the head of 

 steamboat navigation on the Saguenay, as well as all the way to Chicou- 

 timi, twelve miles further up the river. It was not, however, found at 

 Tadousac at the mouth of the Saguenay. We know by its subsequent 

 record that it must have spread westward and especially southward by 

 1866, and it was indeed taken at Brome township within a dozen miles 

 of the Vermont border by the Kev. T. W. Fyles. Dr. G. Dimmock 

 speaks of it as found this year also in northern New Hampshire and Ver- 

 mont, but without specification, and Dr. J. C. Merrill reports the capture 

 of a single specimen in the White ^Mountains ; that it must have invaded 

 these two states this year is certain from the considerable niunbers found 

 the year following. I have accordingly drawn the curve of its distribution 

 to include this northern area. Moreover, it is certain that it had reached 

 this latitude in Maine, for there is a specimen in the Yale College Museum, 

 which was taken by Professor S. I. Smith in Norway, Maine, in 18(55, 

 the earliest ret^ord of its capture in the United States. Probably it had 

 covered the larger part of Maine wherever in the wilderness it could find 

 a patch under cultivation, for writing from Garland in Penobscot Co., 

 under date of Aug. 23, 1869, Mr. H. C. Preble says that he has "not 

 been able to raise a respectable cabbage for some four or five years, on 

 account of the ravages of this species of voracious rascals." Even if we 



