INTRODUCTION. 
Of the articles which compose this bulletin, three relate to Mexican 
insects, one specifically to Japanese insects, and two to insects which 
enter the port of San Francisco, mainly from Japan but also from other 
Pacific ports, principally those of Hawaii and Australasia. In a paper 
read before the Peninsula Horticultural Society, at Dover, Del., on Jan- 
uary 11, 1895, and published in Insect Life (vol. vn, pp. 332-339), the 
writer called especial attention to the great and constant danger of the 
importation of injurious insects new to the United States, and sounded 
an especial note of warning regarding the Mexican border. One of 
his first official acts on assuming charge of the Division of Entomology 
in June, 1894, was to secure the temporary appointment of Prof. C. H. 
Tyler Townsend to conduct a brief investigation of the injurious 
insects of northern Mexico which are liable to be carried across the 
border, and the first three papers of this bulletin give the technical 
results of this short investigation, the first paper, by Professor Town- 
send himself, possessing also some popular interest. The whole subject, 
as a matter of fact, is one which deserves popular as Avell as technical 
treatment, and a popular summary may be given at another time. Our 
danger from Mexico is fast becoming realized. A great influence in 
bringing about popular appreciation of this danger has been the advent 
in Texas cotton fields of the Mexican cotton boll weevil, Anthonomus 
grandis, and quite recently resolutions have been adopted by the Board 
of Control of the New Mexico Agricultural Exf>erinient Station, recom- 
mending the stationing of horticultural quarantine officers at southern 
ports and the appointment of an agent of this Department to study 
injurious insects in Mexico, Central America, and the West Indies. 
There is fortunately not the same danger of the importation of 
injurious insects from Japan and the Pacific islands that there is from 
Mexico. This is largely owing to the excellent legislative acts which 
are in force in California and to the work of the State Board of Hor- 
ticulture. It is necessary, however, for even the executive officers of 
the State Board of Horticulture of California to be familiar with the 
insects which are liable to be imported, and it was with this fact in 
view that my predecessor in office, Prof. C. V. Riley, secured the serv- 
ices for a short time of Mr. Otoji Takahashi, a Japanese entomologist 
who had been trained by Prof. J. H. Comstock at Cornell University, 
to conduct a short investigation, particularly of the scale insects affect- 
