. Zoology : for students and general readers . Zoology. Pig leg of male JCulim- nadia nus a, hand ; b, end of body. This suborder presents a beautiful series of increasingly complex forms, as we ascend from Limnetis to Branchipus. In Limnetis the bivalve shell encloses the ani- mal, and is the size of a small flattened pea. There are from ten to twelve feet - bearing segments. L. GoiihlU Baird (Fig. 243) is very rare in Canada and New England. The shell of Linmadia is thin, oval, and there are from eighteen to twenty-six feet-bearing segments. L. {Eulimnadia) Agassizii Packard (Fi
. Zoology : for students and general readers . Zoology. Pig leg of male JCulim- nadia nus a, hand ; b, end of body. This suborder presents a beautiful series of increasingly complex forms, as we ascend from Limnetis to Branchipus. In Limnetis the bivalve shell encloses the ani- mal, and is the size of a small flattened pea. There are from ten to twelve feet - bearing segments. L. GoiihlU Baird (Fig. 243) is very rare in Canada and New England. The shell of Linmadia is thin, oval, and there are from eighteen to twenty-six feet-bearing segments. L. {Eulimnadia) Agassizii Packard (Figs. 344 and 245) inhabits pools in Southern New En- gland. The shell of Estlieria (Fig. 246, Es- theria Belfragei Packard) is sometimes mis- taken for that of the fresh - Avater moUusks Cyvlas and Pisiditmi. The males of the fore- going genera have the first pair of feet modi- fied to form large claspers (Fig. ). In Apus the abdomen projects beyond the large carapace, and ends in two long many-jointed appendages. There are about sixty pairs of feet, each foot divided into several leaf-like lobes, wherein respiration is carried on. Tliese Pliyllopods usually swim upon their backs, as in the species of Bran- chipus. The females chiefly differ from the males in the presence of an orbicular egg-sac on the eleventh pair of feet, the sac being a modification of two of the lobes of the feet, and containing but a few eggs. A^ms mqualis Packard (Fig. 347, Fig. 249 A, represents the larva of a European Ajms) inhabits pools in the western plains. Lepidunis differs from Apns in having the telson spoon-shaped instead of square. L. C'ouesii Packard (Fig. 248) occurs on the Rocky Mountain plateau in Utah and Montana. It is an interesting fact in zoo-geography that there are no species of Apus and Lepidunis east of the west- ern plains. Apiis has been found by Siebold to reproduce parthenogenetically. The various species of Branchijms end Artemia have no. Fig. 246.—Shell oiEstherla Belfr
Size: 1878px × 1331px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, booksubjectzoology, bookyear1879
