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Biometrical Observations on Shells of Limnaea Species

Published online by Cambridge University Press:  05 June 2009

B. G. Peters
B. G. Peters
Affiliation:
Principal Research Assistant, Institute of Agricultural Parasitology, St. Albans
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Extract

1. In differentiating between species of snails various ratios of shell dimensions are frequently used as biological constants descriptive of the species. Some of the ratios commonly used are: length to breadth (L/B), length to length of body-whorl (L/W), length to length of shell aperture (L/l), and length of shell aperture to its breadth (1/b). Mean and extreme values of these ratios are given for small samples of five species of Limnaea.

2. In L. palustris the least variable of these simple ratios is L/W and the next best is L/l. Statistics are given for the distributions of these two ratios.

3. Data collected by Mozley are used to show that in L. palustris the ratio L/l (at least) is subject to considerable local variation, a fact which detracts from its value as a species constant.

Type
Research Article
Information
Journal of Helminthology , Volume 16 , Issue 4 , December 1938 , pp. 181 - 212
Copyright
Copyright © Cambridge University Press 1938

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References

REFERENCES

Ellis, A. E., 1926.—“British snails. A guide to the non-marine Gastropoda Great Britain and Ireland, Pliocene to Recent.” Oxford. 275 pp.Google Scholar
Fisher, R. A., 1936.—“Statistical methods for research workers.” Edinburgh, 6th Edition. 339 pp.Google Scholar
Mehl, S., N.D., [1932 ?].—“Die Lebensbedingungen der Leberegelschnecke (Galba truncatula Müller).” Arb. buyer. Landesanst. PflBau., No. 10, 178 (W.L. 1627a.)Google Scholar
Mozley, A., 1935.—“The variation of two species of Lymnaea.” Genetics, xx 452–465. (W.L. 9023.)CrossRefGoogle Scholar
Nomura, E., 1927a.—“An application of a=kbx in expressing the growth relation in the freshwater bivalve, Sphaerium helerodon Pils.” Sci. Rep. Tôhoku Univ. (4), II, 57–62. (W.L. 19959.)Google Scholar
Nomura, E., 1927b.—“Further studies on the applicability of a=kbx in expressing growth relations in molluscan shells.” Sci. Rep. Tôhoku Univ.Google Scholar
Reichmuth, W., 1936.—“Die Leberegelschnecke Galba truncatula Müll. Zugleichein Beitrag zur Systematik der Siisswasserschneckenfamilic Lymnaeidae.” Z. Morph. Õkol. Tiere, xxxi (2), 207–244. (W.L. 23512a.)CrossRefGoogle Scholar
Sasaki, K., 1927.—“On the growth relation in Earshclls.” Sci. Rep. Tôhoku Univ. (4), ii, 197–208. (W.L. 19959.)Google Scholar
Teissier, G., 1931.—“Recherches morphologiques et physiologiques sur la croissance des Insectes.” Trav. Sta. biol. Roscoff, Fasc. 9, 27–238. (W.L.21765a.)Google Scholar
Wigglesworth, V. B., 1934.—“Insect physiology.” London. 134 pp.Google Scholar