five Imtterflios each minute, the ground being strewn with the 

 discarded wings. 



The first migration of this l)utterfiy was recorded by Behr 

 (3) and took place on November 15, 1856, flying south-south- 

 east; they did not crowd into swarms but flew singly, at a 

 great height ; they were seen up to the 18th of the month. 



The second migration took place, as recorded also by Behr, 

 in the fall of 1864, but did not reach San Francisco; it was ob- 

 served by J. G. Cooper at Lake Tahoe ; in Oregon (Gabb) ; it 

 was reported as numerous, but going in no special direction; 

 north of Marin County there were large swarms flying south ; 

 and near Tamalpais they were also numerous. 



The third migration is recorded by Henry Edwards (4), 

 or rather the remarkable abundance of larvae on Ceanothus 

 bushes on Tamalpais, in May, 1875, millions of them; but the 

 following fall appearance of the butterflies w^as not recorded 

 or observed ; l)ut must have taken place. 



Tile fourth migration was recorded by C. L. Hopkins (5). 

 ''During an ascent of ^It. Shasta, made August 29, 1889, a most 

 interesting occurrence was noted in the flight of countless 

 myriads of butterflies (Vanessa Californica) at an altitude far 

 above snow-line." The flight was in a southeasterly direction, 

 and in tii(^ greatest numbers at six or eight hundred feet below 

 the summit (11,000 or 12,000 feet). "The fact of its being a 

 continuous flight of these insects across the mountain in one 

 direction during the warm part of the day — a period of nearly 

 Ave hours — is beyond question." It was probably in progress 

 one or two days i)revious, from the fact that numbers were 

 found dead among the rocks and stones stiffened by the cold. 

 How much longer it continued, there w^as no means of knowing. 



The flfth period of a])undance, recorded or observed, was in 

 1902; but we have little data for this time. Bryant speaks of 

 it, but says it was much less than the year 1911. I remember 

 ]\[iss Alice Eastwood speaking of great swarms on "Sit. Tamal- 

 l)ais in the fall of 1902, at the luncheons in the herbarium room 

 of the Academy in San Francisco, with Dr. Behr, Miss East- 

 wood and the writer. ]\Ir. F. X. AVilliams (7) recorded it as 

 fairly swarming in Shasta County in 1902 ; and Mr. J. E. Brown 

 and the writer found it in the mountains near Pasadena during 

 the summer of tliat year, but rare since then. 



The sixth recorded migration, of which we have the most 

 data, and of which v^e have referred in the work of Bryant 

 (6), occurred during the year 1911. Coolidge reported them 

 common and flying southward in the San Joaquin Valley ; New- 

 comer recorded them in remarkal)le a1>undance in the Sierra 

 Nevada Mountains near Lake Tahoe in July and August, and 

 at Palo Alto in October; Clemence took two and saw others 

 in his yard in Pasadena on March 14 and later; the writer took 

 several and noted them as being common in June in the San 

 Gabriel Mountains, near Pasadena; and Haskin noted them 



