The Growth of the Shell of <i>Patella vulgata</i> L

Abstract

Summary. The breeding‐season extends from July to January. Sexual maturity is reached at a length of 20–25 mni. An merage size for a limpet of the last season's brood in Janiinry or February is 10 mm. A t the end of the first year it mag be 29 mm. long. Probable sizes at the end of the second and subsequent years are 38 mm., 44 mni., 48 mm., 53 mm. Shells over 50 mm. may be considerably more than five years old. Sexual maturity is reached in the first year, and when the linipet is only half‐grown. The rate of growth decreases with age and maturity. It is slower during the colder months of the year. Considerable changes take place in the ratios of the shelldimensions during growth. These changes are probably in large part the expression of laws of growth, and not due to natural selection,