. Zoology : for students and general readers . Zoology. 18 ZOOLOGY. ductive nucleus, and several contractile vesicles, rudely an- ticipating the heart of higher animals. Protozoans repro- duce by self-division and the formation of motile germs (zoospores), and in the Infusoria of ciliated young. There is thus a great range of forms leading from the most primi- tive type (Protamceba) to the most specialized forms, such as the bell animalcule (Vorticella.) Class I.—Monera (Moners). General Characters of Moners.—This group comprises the simplest forms of Protozoans, whence the name Monera (/AovT^
. Zoology : for students and general readers . Zoology. 18 ZOOLOGY. ductive nucleus, and several contractile vesicles, rudely an- ticipating the heart of higher animals. Protozoans repro- duce by self-division and the formation of motile germs (zoospores), and in the Infusoria of ciliated young. There is thus a great range of forms leading from the most primi- tive type (Protamceba) to the most specialized forms, such as the bell animalcule (Vorticella.) Class I.—Monera (Moners). General Characters of Moners.—This group comprises the simplest forms of Protozoans, whence the name Monera (/AovT^psi, simple). The lowest forms are almost identical in appearance with the lowest plants, and they can only. Fig. 8.—P>otomonm amyli, greatly magnified, ^ encysted; x, germs or zo- ospores ; y. food-masp. B, germ freed from the parent-cyst. C, D, older germs. E, adult encysted :y, food ; s, projection Inward of the cell-wall; x, wall of tie cyst; t, germs.—After Cienkowski. be claimed to be animals from their resemblance to higher forms leading to Ammha, which, in turn, is connected by a series of forms leading to undoubted animals, such as the shelled Ehizopods (Fig. 14). The Monera differ from the Khizopods {Ammia, etc.) in wanting a nucleus and contractile vesicles. Their body- substance is homogeneous throughout, not divided into a tenacious outer and softer inner mass, as in Amceba. They move by the contraction of the body, and the irregular pro- trusion of portions of the body forming either simple pro- cesses {pseudopodia) or a network of gelatinous threads. The food, as some diatom, desmid, or protozoan, is swallowed. 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 Packard, A. S. (Alpheus Spring), 1839-1905. New York : Henry Holt
Size: 2205px × 1133px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, booksubjectzoology, bookyear1879
