. A manual of zoology. Zoology. III. AXXELIDA; organic tubes in -ivhich foreign matter may be incorporated or which may be calcified. The worms project their anterior segments from the tubes. The Errantia often burrow, but from time to time swim about preying on other ani- mals. Correlated with habits are differences in structure. In the Errantia the head and trunk are not very different; the anterior part of the alimentary tract can be protruded as a proboscis, and, corresponding to their predaceous habits, is often armed with strong jaws (fig. 260). The Sedentaria have no such tee
. A manual of zoology. Zoology. III. AXXELIDA; organic tubes in -ivhich foreign matter may be incorporated or which may be calcified. The worms project their anterior segments from the tubes. The Errantia often burrow, but from time to time swim about preying on other ani- mals. Correlated with habits are differences in structure. In the Errantia the head and trunk are not very different; the anterior part of the alimentary tract can be protruded as a proboscis, and, corresponding to their predaceous habits, is often armed with strong jaws (fig. 260). The Sedentaria have no such teeth, but there is a greater difference between anterior and posterior somites. In the latter the parapodia are weakly developed, and this part resembles the Oligochfctes in appearance. The head and beginning of the trunk (lliorax) are richly pro\'ided with gills and tentacles for respiration and taking food (fig. 261).. Fig. 263.—New England Annelids ffrom Emerton and Verrill). ,1, male Autolytus; B, Sternaspis fossor; C, Cistenldes gouldii; D, Clymene torquata. Sub Order I. ERRANTIA. Predaceous annelids with strongly armed pharynx. The EuxiciDiE, mostly represented on our shores by small species, contains some species a yard in length. Diopalra* Nothria* Alciopid.^, transparent, pelagic, with large, highly developed eyes (fig. 84). The Syllid^ usually have three long tentacles; Autolylus'' (fig. 263), Myrianida* (p. 275). The ;* {Lepidonotus* Polynoe* (fig. 262), are bottom forms with elytra. Nereid.^;; Nereis virens,^- clam worm of all northern seas. Sub Order II. SEDENTARIA (Tubicola). These cannot wander, but live in tubes. , tube is membranous and there is a crown of gills; Alyxicola,'* Chonc* Manyunkia* Serpulid^, tube calcified and closed by an. 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 ori
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectzoology, bookyear1912
