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Show 78 Utah Academy of Sciences, Arts and Letters [Vol. XV, daily observation for 28 days. During this time it consumed 422 fourth in star aphids, or an average of approximately 15 aphids per day; 21 were eaten during the last twenty-four hour period that the predator was under obser vation, 7 being the fewest eaten during any similar period. Individual no, 2 pupated in 17 days, after eating 106 aphids, and was under observation as an adult for 26 days. During this time it consumed 443 fourth instar pea aphids, or an average of about 17 aphids per day. On the third day this female lady bird did not eat any aphids, but on the fourteenth to seventeenth days of ob servation, respectively, 25, 29, 25, and 30 aphids were consumed as food. On the twentieth day the above female was caged with the male and copulation occurred immediately. During the time the two beetles were caged together, 30 aphids were eaten. On the following day, the female deposited fourteen eggs in her cage. 'Hippodamia 13-punctata (P.). A larval ladybird beetle collected from aphids in a pea field at Springville, was reared in the laboratory. The adult was caged in the insectary and fed upon fourth instar pea aphids from June 29, 1937, to August 1. During this time 199 aphids were destroyed, or an Fourteen aphids, average of approximately 5.85 aphids for each day. eaten on the thirteenth day, were the maximum number consumed in any twenty-four hour period. The striped ladybird beetle. A ladybird larva, collected among pea aphids at Springville, became a striped ladybird beetle, Ceratomegilla vitti The adult fed upon 202 fourth instar pea aphids during the gera (Mann.). thirty-four day period it was under observation; this was an average of ap proximately 5.94 aphids eaten per day. The most aphids eaten in a single day by this adult were 15; during one day no aphids were consumed. Chrysopidae, Adult Chrysopidae, or green lacewings, and their larvae, the aphis lions, were less abundant in pea and alfalfa fields than ladybird beetles and syrphid fly larvae, but those present were highly effective predators of the pea aphid. Both adult and larval stages were predacious in the species studied. Adult females laid eggs on the sides of glass tumblers, in which they were caged with aphids as their food supply. Eggs were hatched over a pan of water, the larvae being reared in one-inch glass cylinders, as used for the syrphid larvae. One aphis lion,· hatched in the laboratory, ate 56 fourth instar pea aphids in the twelve days before pupation occurred, or an average of approximately 4.66 per day, ten fourth instar aphids being fed The larva pupated July 5, 1937, and the upon and killed on the tenth day. adult, Chrysopa oculata separata Bks.t emerged July 27. During the six days following emergence this adult consumed from 18 to 28 aphids daily, totaling 127 fourth instar nymphs. A second larva hatched, pupated, and emerged on the same days as the above, consuming 120 fourth instar pea aphids in 12 days. On two of the days, 20 aphids were fed upon. Upon emergence, the adult Chrysopo: o. separate Bks. ate 112 fourth instar aphids in six days. Because of the quite common belief that adult lacewings take no fo.OO, the writers were especially interested to see these adults chrysopids consumng from 17 to 28 fourth instar pea aphids each day. When placed in a rearmg cage with five aphids, the adult immediately attacked one of these large nymphs and completely devoured it. In less than three minutes, all 5 fourth Three additional aphids were supplied, two instar aphids were consumed. being completely consumed, and the third being left as a chewed exoskeleton. An adult lacewing was observed under a good wide-field binocular mic,:o among . scope as it walked 4 part way across a Petri dish before it encountered a thIrd Determined by A. B. Gurney of the United States Bureau of Entomology and Plant Quarantine. |
