. Zoology : for students and general readers . Zoology. Fig. 181.—Development of Bentalhnn. A, morula ; B, trochosphere ; C, annu- lated larva ; D, larva with its rudimentary shell; z, velum ; a, shell; E, young much farther advanced, the shell or hody segmented ; d\ rudimentary tentacles ; j, sub- ce.^ophageal nerve-ganglia; //", digestive canal, and liver (/'); the foot protrudes from the shell. All magnified.—After Lacaze-Duthiers. Dentalium are distinct. The young is a trochosphere and afterwards becomes segmented, and the univalve shell then appears. (Fig- 182.) Order 2. Pteropoda.—I
. Zoology : for students and general readers . Zoology. Fig. 181.—Development of Bentalhnn. A, morula ; B, trochosphere ; C, annu- lated larva ; D, larva with its rudimentary shell; z, velum ; a, shell; E, young much farther advanced, the shell or hody segmented ; d\ rudimentary tentacles ; j, sub- ce.^ophageal nerve-ganglia; //", digestive canal, and liver (/'); the foot protrudes from the shell. All magnified.—After Lacaze-Duthiers. Dentalium are distinct. The young is a trochosphere and afterwards becomes segmented, and the univalve shell then appears. (Fig- 182.) Order 2. Pteropoda.—In these winged-snails the head is slightly indicated and the eyes are rudimentary ; while they are easily recognized by the large wing-like appendages {epipodiuni), one on each side of the head. The shell is conical or helix-like. The species are hermaijhroditic. C'avolina tridentata Lamarck and Styliola vitrea Verrill (Fig. 183) are pelagic forms, occurring on Fig. t]ie high seas, and are occasionally taken with the talivm Indiana- , «. ,i „ tit -n n -i rmn. Used as tow-net Oil the Southern coast of JNew England. shell money. — . .•-n-u-jjii • ? i After Stearns. Limacina circtica Fabr. is of the size of, and looks like, a sweet pea, moving up and down in the water. It is common from Labrador to the polar 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: 884px × 2829px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, booksubjectzoology, bookyear1879
