464 EXPERIMENT STATION RECORD. 



for the operation. In 1908, the first larvfe were noted about the middle of 

 June; in 1909, they began to emerge about May 20 and continued to appear 

 until after July 1. For several days after hatching the young caterpillars re- 

 main massed about the remains of the eggs, feeding occasionally on the empty 

 shells. The processional habit is persisted in until the third larval instar. 

 " Observations made in the open appear to show that the first 3 instars are 

 passed in rapid succession, each one lasting less than 2 weeks. The fourth 

 instar is longer, while the fifth is indefinitely long, averaging at least 4 weeks." 



The author finds that they eat nothing but grass, and only the native grasses. 

 Individuals placed upon timothy, blue grass, and various grains, wheat, oats, 

 and barley, refused them entirely. A list is given of 13 species of Graminae 

 upon which they were found feeding. The earliest date that the caterpillar 

 has been observed to spin up is August 18. " Where weeds are not available 

 for pupation, clumps of grass are used, their stems being often drawn together 

 by a mass of webs until they resemble in shai^e an Indian tepee. When both 

 weeds and grass stems are wanting, the larvte burrow under the short grass 

 close to the ground and draw the blades together for what little protection 

 they will afford." 



The duration of the pupal stage was found to be from 5 to 8 weeks and even 

 longer, varying under similar conditions. In 1909, the first adults to emerge 

 were observed on October 1. They continue to appear until the middle of 

 November, unless as in 1909, the cold and snow puts an earlier stop to their 

 emergence. It is said that the life of the individual moth rarely if ever exceeds 

 3 days. 



In order to determine the percentage of parasitism. 5,000 pupse were col- 

 lected during September, 1909, and dissected. Of these 56.4 per cent were found 

 to be males and 43.5 per cent females, 95 per cent being alive and 5 per cent 

 dead, and only 30, or 0.6 per cent being parasitized. The parasites found were 

 Pimpla conquisHor (1), P. sanguinipes (8), Chalcis ovata (12), Tachina mella 

 (6), and unclassified hymenoptera (3). Other enemies discovered were robber 

 flies (Stenopoffon picticornis which feeds upon the caterpillars and Erax varipes 

 which captures the moth), and a small mite {Rhyncholoplms sp.) which occurs 

 at times on larvae. An ant, Monomorium minutum minimum, found in pupal 

 shells is sui)posed to be a scavenger. Robins were observed carrying caterpil- 

 lars away and occasionally feeding upon them. 



Remedial measures considered include burning of the range, introduction of 

 natural enemies, and rolling the ground. It is said that at the time the infesta- 

 tion is most severe there is usually insufficient grass remaining to support a 

 running fire. "An experiment in this line was tried in the spring of 1909 and 

 a large area in a wild pasture near Koehler was burned over. Within this 

 burned area, later in the season, the number of caterpillars equaled those of 

 the surrounding unburned parts of the same pasture." The author is of the 

 opinion that at the present time burning the range would be only a temporary 

 and local expedient. The most serious objection to any scheme of destruction 

 that involves either labor or expense is found in the extremely small value per 

 acre of the grass crop, the land renting from 2 to 5 cents per acre for the. year's 

 pasturage. 



Catalogus dipterorum, C. Keet^sz (Catalogus dipterorum. Budapest, 1910, 

 vol.7,pp.Jf70).—ln this volume the Syrphidse, Dorylaida;, Phoridaj, and Clythi- 

 idse are listed. For the preceding volumes, see a previous note (E. S. R., 22, 

 p. 656). 



A catalogue of the Coleoptera (Colcoptcroruni Catalogus. Berlin, 1910, pts. 

 5, pp. 31; 6, pp. 81; 7, pp. 57; 8, pp. 70; 9, pp. 68; 10, pp. 10; 11, pp. JfO ; 12, 

 pp. 68; 13, lip. 21; U, pp. 25; 15, pp. 166).— A continuation of the catalogue 



