The royal natural history . e parapodia of the second segment unite with those of the first to form adorsal crest, and between these and the lower branches the skin is much swollenand of a violet colour: the following; three segments are swollen and haverelatively short parapodia. Species of these worms are found on the coasts ofNormandy and in the Mediterranean. Like many other marine animals, thisworm is phosphorescent, the phosphoric matter spreading like a cloud in the the next group the gills are in the form of small trees or branches ofthreads attached to the end of the head; wh
The royal natural history . e parapodia of the second segment unite with those of the first to form adorsal crest, and between these and the lower branches the skin is much swollenand of a violet colour: the following; three segments are swollen and haverelatively short parapodia. Species of these worms are found on the coasts ofNormandy and in the Mediterranean. Like many other marine animals, thisworm is phosphorescent, the phosphoric matter spreading like a cloud in the the next group the gills are in the form of small trees or branches ofthreads attached to the end of the head; while the mouth is unprovided withcither teeth or a proboscis. The creatures spend their days in tubes, fromwhich they can only be extracted by force. In Hermella the body ends ina long unjointed, limbless, hairless tail, while the rest of the body bears well- ANNELIDS. 43? developed bristly parapodia, upon the upper side of each of which there is atongue-shaped gill. The head is remarkable in that the two large feelers blend. \ \ tube-worm {Eermella). into one and bear a few rows of broad,flat bristles. They are thus convertedinto a stopper, which closes the mouthof the tube when the worm is Terebella, forming the family Tere-bellidcB, the tubes are formed of frag-ments of sand or shell. In the family SerpuUdce the gillsare restricted to the fore-part of thebody, and the water set in motion bytheir glistening hairs brings the foodto the mouth, which is situated immedi-ately beneath. The head-lobe is blended with the first segment, and not sharplymarked off from it, as in most of the worms hitherto described. These animalslive in calcareous (chalky) tubes, the apertures of each tube being closed—whenthe worm has retreated within—by a tight-fitting stopper, formed from a modifiedpiece of one of the gills. The first tube made by the young worm is cylindrical /(hcetopterus. s 43« WORMS. and open at both ends, but as the animal increases in size it enlarges and exte
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Keywords: ., bookcentury1800, booksubjectnaturalhistory, booksubjectzoology
