124 PROCEEDINGS OF THE CALIFORNIA 



V. Califomica is remarkable from its being one of the few wandering Lepi- 

 doptera yet known. The first migration I observed was on November 15th, 

 1856, when numbers of this butterfly flew over San Francisco in a general 

 direction of south-south-east. They flew singly, and never crowded into 

 swarms. Most of these butterflies passed over our streets at too great a height 

 to permit close inspection — a few alighting here and there on lamp-posts, sign- 

 boards, or in the more rural parts, on flowers. It was from these that I 

 obtained the specimens in my collection. They nearly all looked worn and 

 shattered, and there were no fresh specimens among them : clearly indicating 

 that they were not raised in the neighborhood of the city, but had come 

 from distant parts. On the 18th some of the stragglers were still to be seen, 

 but on the 19th they had all disappeared. The second migration took place 

 last fall, but did not reach San Francisco. I received a series of specimens, 

 caught by Dr. Cooper, on the road to Lake Taho. Others I received from 

 Oregon, where they were collected by Mr. Gabb, during his geological exam- 

 ination of those northern regions. Neither Dr. Cooper nor Mr. Gabb observed 

 any marked direction in the flight of these butterflies ; they agree that the 

 species was strikingly numerous. Mr. Gabb represents it as settling on the 

 ground in dry arroyos, very shy, and when frightened, always returning to the 

 same spot — a behavior which pretty nearly corresponds with that of the nearest 

 relative, the European V. Polychloros. Both of these authorities prove merely an 

 unusual number of this butterfly at an unusual time of the year. The descrip- 

 tion of the habits of the insect, as observed by Mr. Gabb in the Umpqua Val- 

 ley, show clearly that there it felt at home. By comparing notes received from 

 Mr. Johnson, of Marin County, I have come to the conclusion that the country 

 to the northward, crowded with this Vanessa, must have sent at least one colony 

 south ; and I was told by the above-mentioned gentleman, the statement being 

 confirmed by several intelligent farmers of the same neighborhood, that large 

 numbers of a brown butterfly had come from San Quentin, and crossed over 

 that part of the bay which stretches between San Rafael and Saucelito. 

 About the same time, great numbers of the same insect were observed in Lagu- 

 nita Valley, at the base of Tamal Pais, where the swarms gathered in a great 

 crowd, and disappeared as suddenly as they came. 



I trust that my loquacity in regard to the habits of this species will be par- 

 doned. I consider the observation of facts touching the migration of animals, 

 of the highest importance, and think it desirable that all observations on these 

 points should be put on record : so that hereafter, when a sufficient number of 

 instances may have been collected, conclusions may be drawn, and perhaps many 

 hitherto inexplicable points in the geographical distribution of insects, and of 

 organic life in general, may be explained. 



This butterfly is rather rare in common years, and is, perhaps, notwithstand- 

 ing its name, V. California!, not exactly an indigenous species, at least not in 

 the middle counties of our State. Unlike all other Vanessida known to me, it 

 has but one generation, at least in California, where the imago is always found 

 late in the season. I do not venture to decide whether V. Califomica requires 

 a longer time for development in the larva state than the other Vanessida, or 



