106 Bulletin American Museum of Natural History (Vol. LIII 
Limneus subgenus Eulimneus SANDBERGER, 1875, ‘Land- u. Siisswasser-Conch. 
Vorwelt,’ pp. 787 and 844. Monotype: Helix stagnalis Linnzus. 
Lymneus Brarp, 1815, ‘Hist. Coq. Terr. Fluv. Env. Paris,’ p. 133. Different 
spelling of Lymnza. 
Limnza DE BUAINVILLE, 1825, ‘Manuel Malacol. Conchyl.,’ p. 448. Different 
spelling of Lymnexa. 
In the Ethiopian Region the Lymnzxzxe seem to avoid the rain forest 
belt and have not yet been recorded from Upper Guinea, though one 
species has been found in Senegal. In the Belgian Congo they prefer 
ponds of quiet or semi-stagnant water, which may disappear during 
seasons of drought, the animals then burying themselves in the mud. 
Being provided with a lung, many species can survive droughts for con- 
siderable periods and some of them even leave the water voluntarily, 
remaining a time on reeds or stones. On the other hand, they may stay 
under water a long while, either breathing through the skin, which is 
abundantly provided with blood vessels, or filling their pulmonary 
cavity with water, or absorbing the air present as bubbles at the surface 
of aquatic plants.!. These facts are of importance in a consideration of 
these snails as intermediate hosts of certain fluke diseases. 
Most species of Lymnea normally are vegetarians, but all of them 
seem to take at times to a carnivorous diet and certain forms appear 
to prefer flesh to vegetable food. They are hermaphoditic and are 
believed to be capable of self-fertilization. Many eggs are laid together 
in irregular, gelatinous masses, on stones, sticks, leaves of water plants, 
Clr: 
Excepting two or three forms referable to the subgenus Galba, all 
known lymneeids of the Ethiopian Region and Madagascar are fragile, 
Succinea-like forms belonging to Radix.2 This group inhabits nearly all 
of Europe and Africa, and a large part of Asia.’ 
Subgenus GaLBa Schrank 
Galba SCHRANK, 1803, ‘Fauna Boica,’ III, 2, pp. 262 and 285. Monotype: 
Galba pusilla Schrank. 
1Pauly, A. 1877. ‘Ueber die Wasserathmung der Limneiden.’ (Munich), 47 pp: 
_ Willem, V. 1896. ‘Observations sur la respiration cutanée des Limnées et son influence sur leur 
croissance.’ Bull. Ac. Sci. Belgique, (3) XXXII, pp. 563-577. 
_ This relationship has already been recognized by many authors. It is now confirmed by examina- 
tion of the soft parts. 
*In contour the shells of some African forms appear close to the Indian series of L. acuminata 
Lamarck: but the latter differ conspicuously in texture, being more solid and polished, and probably 
are not closely related to the Africans. We consider them a separate subgenus, to which the name 
Cerasina Kobelt may be applied, the type being Lymnza bulla Benson. 
4P. Hesse (1923, Archiv. f. Molluskenk, LV, p. 195) has rejected Galba on the ground of insufficient 
definition. Its type and only species was not originally stated to be Buccinum truncatulum O. F. Miiller, 
which Schrank has on a succeeding page, but Galba pusilla Schrank, said to be smaller than a grain of 
millet, of three whorls, etc. It was evidently a quite young shell, which has been somewhat optimistic- 
ally identified as Lymnea truncatula (Miller). It was not figured, and this identification cannot well be 
either proved’or refuted. If Galba be rejeeted, L. truncatula and its allies will form the section Fossaria 
Westerlund, in the subgenus Stagnicola ‘‘ Leach”’ J effreys. 
