394 



Thrips occurred that year on the leaves of onions in astonishing num- 

 bers, tlie result of their eating being visible in the form of small 

 yellow spots, increasing in size until the tips of the leaves became 

 yellow or brown, the whole stalk finally having a whitish appearance, 

 very different from the usual dark green of a healthy onion plant. 



In 1S1)4 Messrs. Sirrine and Lowe, in Bulletin 83, new series, of the 

 I^ew York Agricultural Experiment Station (pp. 680-682), gave an 

 account of. the damage done by this insect to the leaves of cabbage, 

 accompanied by a description and figures of the species. 



Very recently the species has been treated by Messrs. Osborn and 

 Mally, in Bulletin 27 of the Iowa Agricultural College Experiment 

 Station for 1895 (pp. 139-142), under the name of the western onion 

 Thrips {Thrips aUii Gillette). To the list of food plants already men- 

 tioned are added squash, turnip, stone crop, heal-all, blanket flower, 

 cinquefoil, Nasturtium, candytuft, four o'clock, catnip, sweet clover, 

 Rudbeckia, and mignonette. 



The notes of the Department of Agriculture regarding this species 

 show that it was received during 1889 and 1891 from Mr. Coquillett, 

 from Los Angeles, Cal., where it was very injurious to the onions in 

 that section of the State. 



During 1892 a communication was received from Mr. E. D. Kline, of 

 Streator, Lasalle County, 111., complaining that this insect caused much 

 damage to his onions. 



In July, 1891, the same species was received from ]Mr. F. M. Webster, 

 from Wooster, Ohio, with the report that it was making serious havoc 

 m all onion fields in northern Ohio (see also Insect Life, vol. vii, p. 

 206). In August of the same year it was again reported by Mr. Kline 

 as being extremely abundant on all the onions in that neighborhood; 

 that he used to grow five acres of them every year, but that he had to 

 give it up on account of the extraordinary damage caused by them of 

 late years. At the end of the same mouth Mr. Kline wrote again that 

 they were also infesting his melons, remarking that they generally 

 appear first on onions, next on cabbage, then on melons and cucumbers, 

 and later on anything that may suit their taste. 



In my own notes regarding this species I find that it was taken in 

 the District of Columbia and in Virginia, from February till ]!^ovember, 

 during the years 1882 to 1888, on the leaves of onion, cabbage, cucum- 

 ber, and j)arsley, while in 1885 I received the species from Mr. L. Seifert, 

 Segeberg, Holstein, Germany, with the statement that it was very 

 destructive to the garden leek [Allium por rum). 



Up to the present time I have considered this insect to be a new 

 species, though, after carefully examining and comparing the deter- 

 mined European species in my collection with our American insect, I 

 discovered it to be identical with Thrips idhaci Lind., specimens of 

 which were kindly ^ent to me by Prof, K. Lindeman, at the time that 

 he was studying this species, when it was causing much damage to the 

 leaves of tobacco in Bessarabia, South Russia. A full account of its 



