behavioral or locomotory patterns. While the short-term effects on 

 development of two species of Decapoda are described in this paper, nothing is 

 known of the way in which long-term exposure to sublethal concentrations 

 througli a number of successive generations may contribute to mutagenic 

 effects. Within the realm of the chemistry of these compounds, a number of 

 questions also remain unanswered. Several authors have described the rate at 

 which insect growth regulators degenerate within certain natural and artificial 

 environments (16, 18) but none of these studies have investigated the 

 degradation rate in either an estuarine or a marine environment. Most of the 

 research which has been conducted thus far has concentrated on the effects of 

 the intact compound, and no data appear to be available on either the 

 breakdown products which may occur under estuarine conditions, their fate in 

 the natural marine environment, or the way in which they may affect 

 developmental processes of marine invertebrate animals. 



Although it is clear that the juvenile hormone mimics and insect growth 

 regulators may offer great potential as replacements for many of the more 

 persistent pesticides, it seems equally clear that a considerable amount of 

 research remains to be done to assure their proper use within the estuarine and 

 coastal environments. 



ACKNOWLEDGMENTS 



We are grateful to Zoecon Corporation, Palo Alto, California, for providing 

 the pure compound methoprene (Altosid ) and to the Monsanto Corporation, 

 St. Louis, Missouri, for supplying MONO-585 for experimental use. This 

 research was supported by a grant (R-803838-01-0) from the Environmental 

 Protection Agency. 



REFERENCES 



I.Christiansen, M.E., J.D. Costlow, Jr. and R.J. Monroe. 1977a. Effects of 

 the Juvenile Hormone Mimic ZR-515 (Altosid^) on Larval Development 

 of the Mud-Crab Rhithropanopeus harrisii in Various Salinities and Cyclic 

 Temperatures. Mar. Biol., 39:269-279. 



2. Christiansen, M.E., J.D. Costlow, Jr. and R.J. Monroe. 1977b. Effects of 

 the Juvenile Hormone Mimic ZR-5 1 2 (Altozar^) on Larval Development of 

 the Mud-Crab Rhithropanopeus harrisii at Various Cyclic Temperatures. 

 Mar. Biol. 39:281-288. 



3. Costlow, J.D., Jr. 1967. The Effect of Salinity and Temperature on 

 Survival and Metamorphosis of Megalops of the Blue Crab CaUinectes 

 sapidus. Helgolander Wiss. Meeresunters 15:84-97. 



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