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Four hundred (400) adult black-skinned snails, two hundred (200) each of Archachatina marginata and Achatina fulica with weight ranging from 50.42 g to 198.84 g and from 100.10 g to 184.00 g for A. marginata and A. fulica respectively selected based on active appearance, number of whorls and no injury on the foot and/or shell of a base population from a population gathered in the wild within the Niger Delta region were used for the study. Data collected on the selected snails were used to evaluate phenotypic correlations and multiple regression functions which were used for predicting body weights from quantitative traits. Results obtained from the study showed that A. fulica snails with 4 whorls are genetically heavier than A. marginata snails with 4 whorls. This is because there was large and significantly different (P<0.001) disparity in values of measured quantitative traits (mean body weights) among the two breeds. The results of phenotypic correlations among quantitative traits of the two breeds indicated positive, strong and very high significant (P<0.001) correlation coefficients (r p ) between body weight and all body components studied. Whereas for A. fulica snails, there were positive but lower significant (P<0.05) phenotypic correlation coefficients (r p ) between body weight and some body components studied. In fact, there were no significant (P>0.05) phenotypic correlation coefficients (r p ) between shell length and shell 'mouth' width (r = 0.250) and between shell 'mouth' length and shell 'mouth' width (r = 0.187) for A. fulica snails. The prediction equations evolved for body weights of growing snails with 4 whorls using quantitative traits from A. marginata and A. fulica indicated that these quantitative traits, namely; shell length, shell width, shell 'mouth' length and shell 'mouth' width best predicted body weight for A. marginata and A. fulica snails with 4 whorls. The quantitative or phenotypic traits of the two breeds of snail studied could be chosen to differentiate as well as characterize growing snails in the Niger Delta region of Nigeria.

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Data on hatchling body weights and morphometric traits (hatchling body shell length and hatchling body shell width) pertaining to two breeds of snails (A. marginata and A. achatina) from hatch to fourth (4 th ) week of age were analyzed. This was used to obtain correlation coefficient of morphometric traits and to generate prediction equations for live body weight of the animals. Strong, positive and significant correlations between hatchling body weight and body shell width (r=0.82) and between hatchling body weight and body shell length (r=0.80) for A. marginata as well as between hatchling body weight and body shell length (r=0.81) and between hatchling body weight and body shell width (r=0.86) for A. achatina were obtained. Low coefficients of determination (R 2 ) were obtained with the range from 4.73% to 41.30% and from 2.12% to 50.20% for A. marginata and A. achatina respectively. Morphometric traits (Hatchling body shell length and body shell width) best predicted hatchling body weights of A. achatina and not of A. marginata snails. Strong, positive and significant correlations imply that selection for these morphometric traits will lead to improvement of hatchling body weights.