December 9, 1910] 



SCIENCE 



847 



ranged over the greater part of the territory 

 south of the Red River, but for many years was 

 regarded as extinct throughout the interior of 

 Texas. 



Forage Plant Investigations in Mexico: A. S. 



Hitchcock. 



During the summer of 1910, Mr. Hitchcock, 

 systematic agrostologist of the U. S. Department 

 of Agriculture, was engaged in studying and col- 

 lecting the grasses of Mexico and southern Texas. 

 Except for about three weeks spent at San An- 

 tonio, Corpus Christi, Brownsville and Sarita, 

 Texas, the time was spent in the republic of 

 Mexico. AH the states north of the Isthmus of 

 Tehuantepee were visited, except Sonora (visited 

 previously by the speaker), Sinaloa and the Terri- 

 tory of Tepic. Collections were made at the fol- 

 lowing places: Monterey, Saltillo, San Luis Potosi, 

 Cardenas, Tampico, Quergtero, various localities 

 in the Federal District, Popo Park, Mt. Popo- 

 catepetl, Oaxaca, Tomellin, TehuaeSn, Esperanza, 

 Chalchicomula, Alt. Orizaba. City of Orizaba, C6r- 

 doba. Vera Cruz, Jalapa, San Marcos, Pachuca, 

 Balsas, Cuernavaca, Toluca, Acilmbaro, Uruupan, 

 Manzanillo, Colima, Zapotlfin, Nevada Peak, Gua- 

 dalajara, Irapuato, Aguas Calientes, Zacateeas, 

 Torre6n, Durango, Chihuahua, Sanchez and 

 Miiiuea. 



Mr. Hitchcock was accompanied by his son, 

 Frank H. Hitchcock, as assistant, with whose help 

 he was enabled to collect about 20,000 specimens 

 of grasses, of 2,703 numbers. An effort was made 

 to visit the type localities, especially of the earlier 

 collectors. In this way several species were found, 

 which because of insufficient information, have 

 been considered doubtful. Other species supposed 

 to be rare or local were found to extend over a 

 wide range. It appears to be a fact, however, 

 that many species are much more localized than is 

 commonly the case in the United Stat«s. The 

 interior of Mexico consists of a plateau, mostly 

 5,000 to 8,000 feet in altitude, with mountain 

 ranges of higher elevation, the snow-capped peaks 

 of Orizaba and Popocatepetl rising to the height 

 of about 17,500 feet. The northern part of the 

 plateau is arid, the annual rainfall being less than 

 10 inches. The precipitation increases toward the 

 south and in the Sierra Madre Mountains, and 

 reaches a maximum of over 80 inches in the 

 southern part of the state of Vera Cruz. The 

 rainy season usually extends through July, August 

 and September. 



The grasses of the plateau region are smaller 



than those of southern Arizona, many species 

 being common to both. Muhlenbergia, Stipa and 

 Bouteloua are dominant genera. Along the east- 

 ern coast is a strip of lowland, 50 to 100 miles 

 wide, in which the grasses are poorly represented. 

 It is at the juncture of the plateau and the low- 

 land that the grasses are found in greatest pro- 

 fusion. From 1,000 to 4,000 feet altitude, along 

 the sides of the harancas (steep and deep valleys, 

 or cafions) occur numerous species of Panicum, 

 Paspalum and other interesting tropical genera. 

 Of the localities visited, Cardenas, Jalapa, Ori- 

 zaba and Cordoba are situated on the eastern 

 slope of the plateau, and Colima and Zapotlfln 

 on the western slope. At the last two places the 

 genus Tripsacum is especially noticeable, certain 

 species closely resembling in habit our cultivated 

 Indian corn, or maize. 

 Pe<ir Thrips Investigations in. California: A. L. 



QUAINTANCE. 



Mr. Quaintance detailed the present status of 

 the investigations by the Bureau of Entomology 

 of the so-called pear thrips {Euthrips pyri 

 Daniel) in California, illustrating his remarks 

 with lantern slides. It was stated that the insect 

 is now generally present in the deciduous fruit 

 growing areas of Santa Clara, Contra Costa, 

 Alameda and Solano counties, with points of 

 serious infestation in Sacramento, Yolo, Napa 

 and Sonoma counties. According to estimates 

 prepared by Messrs. S. W. Foster and P. R. 

 Jones, the bureau's agents in immediate charge 

 of the work, the losses to the fruit growing in- 

 dustry from this insect to date totalled about 

 $3,500,000, with probabilities for an annual loss, 

 due to its continued spread and increase in de- 

 structiveness of one million dollars. 



Much progress was reported in control measures. 

 It had been determined that in the lighter soils a 

 great deal of good may be accomplished by deep 

 plowing and cross plowing of orchards in the fall, 

 at which time the insect is in the helpless pupal 

 condition and easily destroyed. In the Santa 

 Clara Valley careful records extending over two 

 seasons have shown that about 70 per cent, of 

 the insects may be killed in this way. In other 

 types of soil in which the insects are able to 

 penetrate deeper, in some instances to a depth of 

 24 to 28 inches, but little benefit was found to 

 result from this work. 



It was pointed out that decidedly a most ef- 

 fective method of control of pear thrips was 

 thorough spraying of trees with a combined dis- 



