HISTORICAL STATEMENT. 11 



a complete revolution in so far as the importance of cactus insects is 

 concerned. 



HISTORICAL STATEMENT REGARDING CACTUS INSECTS. 



It has been stated in a preceding paragraph that the insect enemies 

 of Opuntia attracted some attention in former years on account of 

 their injury to the host plant of the cochineal insect. Several of the 

 treatises on the cultivation of the cochineal contain brief suggestions 

 about the destruction of the enemies of the plant, as well as about 

 the enemies of the cochineal itself. In all these considerations, how- 

 ever, only the merest incidental attention was paid to species other 

 than the cochineal. 



The first systematic work on cactus insects that was undertaken 

 was that done in 1895 by Mr. H. G. Hubbard, who lived in Florida. 

 He discovered a lepidopterous larva, Melita/ra prodenialis Walk., 

 which feeds upon the prickly pear, traced out its life history and 

 transformations, and published a most interesting account of his 

 observations. 1 A few years later Mr. Hubbard sojourned for some 

 months in Arizona. In that territory he made studies of the insect 

 fauna of the giant cactus (Cereus giganteus). Although plants of 

 the genus Cereus will probably never be of importance as forage, 2 

 Mr. Hubbard's studies have a bearing upon insects infesting Opuntia, 

 since the faunas of Cereus and Opuntia are largely the same. After 

 his death, the results of Mr. Hubbard's investigations were published 

 under the editorship of Mr. E. A. Schwarz. 3 



From 189G to 1898, on various trips to the region then infested by 

 the boll weevil, Mr. E. A. Schwarz made a number of observations 

 on insects infesting Opuntia. In fact, he discovered a number of the 

 species which have now been found to be of importance in the area 

 in which the prickly pear is undergoing cultivation. Dr. L. O. 

 Howard and Mr. C. L. Marlatt also made observations on cactus 

 insects at about this time. The results of these incidental observa- 

 tions were published in notes in the Proceedings of the Entomological 

 Society of Washington. 



By 1905 Mr. David Griffiths had begun the cultivation of the 

 prickly pear in the vicinity of San Antonio, Tex., and elsewhere. It 

 was on his experimental plantings that the observation was made 

 that the concentration of the plants under cultivation seemed to 

 increase the amount of insect injury. Recognizing the importance 

 of this matter, Mr. Griffiths immediately began the collection of 

 specimens which, with full notes, were transmitted to the Bureau 



1 rroc. Ent. Sue. Washington, vol. ::. pp. 129-1.°,2. two figs., 1895. 



2 The Cereus plants are, of course, utilized in many ways by the inhabitants of the 

 region in which they occur, but not as forage. 



3 Psyche, May, 1899, Supplement, pp. 1-14. 



