. Calosoma sycophanta : its life history, behavior, and successful colonization in New England. Gypsy moth; Browntail moth. INVESTIGATION OF LIFE HISTORY. 43 molted twice in the jars. The mortality for the season of 1909 was 10 per cent of the 8,280 larvae which were fed in this way, and for 1910 it reached 12 per cent of the 8,720 larvae that hatched. It is interesting to compare these figures with those for the year 1908 when a smaller number of larvae was fed individually in jelly glasses provided with cheesecloth covers. A considerable number of larvae escaped by forcing their way through
. Calosoma sycophanta : its life history, behavior, and successful colonization in New England. Gypsy moth; Browntail moth. INVESTIGATION OF LIFE HISTORY. 43 molted twice in the jars. The mortality for the season of 1909 was 10 per cent of the 8,280 larvae which were fed in this way, and for 1910 it reached 12 per cent of the 8,720 larvae that hatched. It is interesting to compare these figures with those for the year 1908 when a smaller number of larvae was fed individually in jelly glasses provided with cheesecloth covers. A considerable number of larvae escaped by forcing their way through the covers and in all per cent of the total for the year (2,854) were either lost or died. This shows that the improved covers used on jars the following years and the experience gained in handling the larvae have resulted in reducing the mortality. Since the work began, July 23, 1907, nearly 20,000 Calosoma larvae have been cared for and most of these have been liberated in the field. In August, 1909, a considerable stock of Calosoma larvae was on hand at the laboratory, and as it seemed advisable to feed and carry them through the larval stages and hibernation where they could be under direct observation they were placed in large box cages (see PL V) set in the ground. These were - 2 by 3-J feet in size, and were provided with a fine wire- netting bottom so that the larvae could not escape. The earth in the cages was 15 inches deep, inches in diameter,. Fig. 18.—Wire-screen hibernation cylinder where larvae of Calosoma were fed in August, 1910. Photographed February, 1911. (Original.) Several cylinders of galvanized iron wire, 17 were also constructed for the same purpose and were sunk in the ground and later stocked with larvae and food. (See fig. 18.) These cylinders were lined on the inside with mosquito netting and the tops and bottoms were made of the same material. One thousand three hundred and eight second and third stage Calosoma larvae were placed in these ca
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Keywords: ., bookcentury1900, bookdecade1910, booksubjec, booksubjectgypsymoth
