357 
We are able to publish, herewith a satisfactory figure of this species 
which was drawn by Miss Sullivan some months ago at Professor 
Riley's direction. We believe it important to publish this figure as 
early as possible in order to assist entomologists in recognizing the 
species should it be found to have established itself at any point in 
this country. 
A REMARKABLE MIGRATION OF BUTTERFLIES. 
Through the kindness of Mr. Geo. W. Knight, of San Marcos, Tex., 
we have received reports of a remarkable migration of the so-called 
snout butterfly, Hypatus bachmani, a species which belongs properly 
to the CaroliDian fauna, but which has been occasionally found as far 
north as Ontario. On September 1 Mr. Knight sent specimens of the 
insect to the Department, and reported that they were flying in an 
eastward direction in vast numbers. At our request he instituted 
inquiries in the surrounding counties as to the occurrence of the spe- 
cies, and ascertained that at about the time mentioned swarms of the 
butterflies were observed flying in a general eastward direction over a 
territory almost one hundred miles square. Taking the city of Austin, 
Travis County, as the northeastern corner of this territory, it may be 
bounded as follows : Westward 75 miles to Fredericksburg. Gillespie 
County: thence due south 100 miles to Pearsall, Frio County; thence 
eastward to Karnes City. Karnes County, 75 miles. The butterflies 
were also reported from the following towns lying within this territory : 
Boerne, Kendall County; Castroville, Medina County; Xew Braunfels, 
Comal County, and San Marcos. Hays County. 
At our suggestion a part of Mr. Knight's inquiry was directed to 
ascertaining the abundance of the hackberry, Celt is occidentalism 
throughout the territory covered by this migration. This is the only 
food plant known for the species, and the reports received by Mr. Knight 
show that it grows more or less plentifully at nearly all the places 
where the migration was observed. 
Hypatus bachmani is a common butterfly throughout Texas wherever 
the hackberry tree grows, but migratory movements of this species 
have never been reported before. It would appear to us that the flights 
observed this season in Texas were brought about by the rather 
abnormal weather of the past season. Mr. Schwarz, who visited Texas 
in August, tells us that during the months of June and July there was a 
period of severe drought all over the State, which was suddenly followed 
in the first week of August by an equally pronounced rainy season of 
several weeks' duration. This very moist and at the same time hot 
weather must have favored the simultaneous issuiug of an unusually 
large number of specimens from their chrysalids and thus brought 
about the primary condition under which migratory instinct is developed 
in many insects. 
12283— Xo. 4 6 
