. A textbook of invertebrate morphology [microform]. Invertebrates; Morphology (Animals); Invertébrés; Morphologie (Animaux). 314 INVERTEBHATE MORPHOLOGY. \ )â ! S J I animals are propelled through the water. In their general form much diversity is observable. In accordance with their pelagic habits the majority are more or less transparent; and some, the Gymnosomafa, Pneumodermay Clione, etc., are entirely destitute of a shell, mantle, and, except in Pneumo- derma and its allies, of a branchia. Others, the Thecosomata, possess these structures, howeverâtL j shell in Limacina being spir
. A textbook of invertebrate morphology [microform]. Invertebrates; Morphology (Animals); Invertébrés; Morphologie (Animaux). 314 INVERTEBHATE MORPHOLOGY. \ )â ! S J I animals are propelled through the water. In their general form much diversity is observable. In accordance with their pelagic habits the majority are more or less transparent; and some, the Gymnosomafa, Pneumodermay Clione, etc., are entirely destitute of a shell, mantle, and, except in Pneumo- derma and its allies, of a branchia. Others, the Thecosomata, possess these structures, howeverâtL j shell in Limacina being spirally coiled, the mantle-cavity situated in front of the. â ^ Pig. 140.âHyalea complanaia (after 6e(;enbaur, from Hertwio). a = anus. m = mantle. br = braucbiae. oe = a?sophagus. c = heart. re = nephridia. O = reproductive organs. » = stomach. h = digestive gland. // = pedal ganglion. visceral hump being without a branchia; in Styliola the shell is not coiled, but is cone-shaped and bilaterally symmetrical, the mantle-cavity containing a gill; while in Cymhidiopsis the original shell is replaced by a cartilaginous case formed by the subepidermal tissues of the mantle, and the voluminous mantle-cavity contains no gill. The head of the Gymnoso- mata carries a non-retractile proboscis, at the extremity of which is situated the mouth, and it may furthermore bear in addition to the tentacles usually present peculiar tentacle- like processes, sometimes provided with suckers and perhaps. 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 McMurrich, J. Playfair (James Playfair), 1859-1939. New York : H. Holt
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishernewyo, bookyear1894
