566 



season upon grass roots again, where they remain all the winter, and 

 they have not been taken upon other plants. The alate form has 

 been taken from 2nd June to 12th July on the roots of Melica hidhosa, 

 Poa prafensis, Phleum nlpinum, and Elymus sp., in Colorado. 



Forda olivacea, Roh., is by far the more abundant of the two species 

 in Colorado, and does considerable damage to grasses and grain every 

 year. It is a very general feeder among the grasses, being most common 

 on isolated clumps along the roadside, the borders of fields and upon 

 ditch banks. The species attacked are cliiefly Hordeiim (sc[uirrel-tail 

 grass), the Agrojnjron spp. (wheat gi'asses) and Kentucky blue grass. 

 It has also been taken on wheat, oats, barley, timothy grass, Bromus 

 inermis, B. tectorum and Ehjmus spp. 



Ballou (H. a.). Spread of the Mexican Cotton Boll Weevil in the 

 United States. — Agric. News, Barbados, xvii, no. 428, 21st 

 September 1918, p. 298. 



Discussing an account published by the United States Department 

 of Agriculture on the present situation with regard to the cotton 

 boll weevil [Anthoiiomus grandis] and its spread during recent years, 

 the author remarks that it is of great interest to cotton growers in the 

 West Indies to note that for a period of twenty-five years the Mexican 

 boll weevil has spread steadily through the cotton belt of the southern 

 States at an average rate of more than 15,000 square miles each year, 

 that the Sea Island cotton districts of Georgia and Florida are invaded, 

 and that the pest has reached South Carolina and at the end of 1917 

 threatened the Sea Island cotton district of that State. The output 

 of Sea Island cotton from those States is bound to suffer a reduction 

 and it is pointed out that, in view of the high cost of production, 

 growers of this class of cotton are likely to turn their attention to the 

 substitution of a more profitable crop. In that case the West Indian 

 cotton growers will be in an increasingly strong position, and it becomes 

 more than ever a matter of national importance to protect the cotton 

 industry throughout the Islands. It is pointed out that A. grandis 

 has within a period of 25 years spread over an area of nearly 500,000 

 square miles and in a few years more will infest the whole of the cotton 

 belt (some 600,000 square miles). This steady spread has been in 

 the face of strenuous exertions to check its increase. The pink boll- 

 worm [Pectinophora gossypiella] has also made extraordinary progress 

 in the past few years and is a pest difficult to control and probably 

 impossible to eradicate. The importation of cotton seed into the 

 Islands from North, South or Central America or any other part of 

 the West Indies is considered dangerous on account of these two 

 pests and is prohibited in most of the West Indian cotton-growing 

 islands. Every help should be given in enforcing the regulations for 

 combating the known cotton pests and for preventing the importation 

 of others. 



Glaser (R. W.). The Polyhedral Virus of Insects, with a Theoretical 

 Consideration of Filterable Viruses generally. — Science, Lancaster, 

 Pa., xlviii, no. 1238, 20th September 1918, pp. 301-302. 



The wilt or polyhedral disease affecting so many different species 

 of insects is not produced by bacteria, but is caused by minute 



