. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. POISONING IN BARNACLES AND MUSSELS 77 variable concentrations could be maintained, the tests which follow were conducted with the citrate. Relation between concentration of cupric citrate and killing time Barnacles With the higher concentrations of cupric citrate in which killing occurred within a few days, adult barnacles all succumbed at about the same time, but at the lower concentration it was difficult to determine accurately when the barnacles should be considered dead. At still greater dilutions of the toxic, it was f
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. POISONING IN BARNACLES AND MUSSELS 77 variable concentrations could be maintained, the tests which follow were conducted with the citrate. Relation between concentration of cupric citrate and killing time Barnacles With the higher concentrations of cupric citrate in which killing occurred within a few days, adult barnacles all succumbed at about the same time, but at the lower concentration it was difficult to determine accurately when the barnacles should be considered dead. At still greater dilutions of the toxic, it was found that most of the animals lived on in a feeble condition for two or three weeks or more. Further- more, there was considerable variation from experiment to experiment, which was no doubt due not only to individual differences in the batches of barnacles, but also -0. 0 02 04 06 08 10 CONCENTRATION OF CUPRIC CITRATE (mgr/hUr) FIGURE 1. The relation between killing time and concentration of toxic for two species of barnacles. to unavoidable changes in the seasonal condition and in the age of the animals. No consistent trend appeared in relation to the latter conditions except that barnacles in the nauplius stage were killed much more quickly than the adults, as noted below. For both B. balanoidcs and B. eburneus, the killing time ranged between two and five days for concentrations of to mg. Cu/liter. At the animals succumbed after ten days. At concentrations of and less, the animals remained alive for two weeks or more. When the reciprocal of the killing time was plotted against the concentration, as in Figure 1, a roughly linear relation was found. The approximate linearity of this relation indicates that the rate of action of the poison is directly proportional to its concentration. The results of a series of tests on the poisoning of nauplii, made on the day of their release from the brood pouch, are shown in Table II. They indicate
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
