. The life of inland waters; an elementary text book of fresh-water biology for American students. Freshwater biology. 178 Aquatic Organisms Melicerta is a large sessile rotifer that lives attached to the stems of water-plants and when undisturbed protrudes its head from the open end of the tube, and unfolds an enormous fo\u--lobed crown of waving cilia. It is a beautiful creatiu^e. Our picture shows the cases of a niomber of Melicertas, aggregated together in a cluster, one case serving as a support for the others. The crown of cilia about the anterior end of the body is the most characterist
. The life of inland waters; an elementary text book of fresh-water biology for American students. Freshwater biology. 178 Aquatic Organisms Melicerta is a large sessile rotifer that lives attached to the stems of water-plants and when undisturbed protrudes its head from the open end of the tube, and unfolds an enormous fo\u--lobed crown of waving cilia. It is a beautiful creatiu^e. Our picture shows the cases of a niomber of Melicertas, aggregated together in a cluster, one case serving as a support for the others. The crown of cilia about the anterior end of the body is the most characteristic structure possessed by rotifers. It is often circular, and the waving cilia give it an aspect of rota- tion, whence the group name. It is developed in an extra- ordinary variety of ways as one may see by consulting in any book on rotifers the figiu-es of such as Stephanoceros, Flos- cularia, Synchceta, Trochos- phcera and Brachionus. The cilia are used for driv- ing food toward the mouth that lies in their midst, and for swimming. Most of the forms are free-swimming, and many alternately creep and swim. Brachionus (fig. 87) shows well the parts commonly found in rotifers. The body is inclosed in a lorica or shell that is toothed in front and angled behind. From its rear protrudes a long wrinkled muscular "foot," with two short "toes" at its tip. This serves for creeping. The lobed crown of cilia occupies the front. Behind the quad-. FlG. 86. Two clusters of rotifers (Melicerta), the upper but little OiUy the cases (none of the animals) appear in the Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Needham, James G. (James George), 1868-1956; Lloyd, John Thomas, 1884- joint author. Ithaca,N. Y. , The Comstock Publishing Company
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfreshwa, bookyear1915
