[Quahog Eggs]:
Fig.15.--Ciliated gastrula, ten hours after fecundation. The embryo Can now swim through the water by means of hairlike cilia. The larger cells have become invaginated.
Fig.16.--Trochosphere stage, twelve to fourteen hours after fecundation. The body has elongated and the cilia are now confined to the front end. The opening of the primitive mouth (pm) cn be seen on the lower side, while above is a slight indentation corresponding to the eginning of the shell gland (sg).
Fig.17.--Formation of the shell, which arises at two symmetrical points of calcification, right and left of the median line, and gradually envelops the animal.
Fig.18.--Early veliger swimmer with velum extended from the shell, about thirty-six hours after fecundation. aa, anterior adductor muscle, pa, posterior adductor muscle, s, stomach, a, anus, mt, mouth, v, velum.
Fig.19.--Veliger slightly older than shown in Fig.18. The intesting (i) has elongated, and the liver (l) is more prominent.
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| Category | Shellfish
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| Caption | [Quahog Eggs]:
Fig.15.--Ciliated gastrula, ten hours after fecundation. The embryo Can now swim through the water by means of hairlike cilia. The larger cells have become invaginated.
Fig.16.--Trochosphere stage, twelve to fourteen hours after fecundation. The body has elongated and the cilia are now confined to the front end. The opening of the primitive mouth (pm) cn be seen on the lower side, while above is a slight indentation corresponding to the eginning of the shell gland (sg).
Fig.17.--Formation of the shell, which arises at two symmetrical points of calcification, right and left of the median line, and gradually envelops the animal.
Fig.18.--Early veliger swimmer with velum extended from the shell, about thirty-six hours after fecundation. aa, anterior adductor muscle, pa, posterior adductor muscle, s, stomach, a, anus, mt, mouth, v, velum.
Fig.19.--Veliger slightly older than shown in Fig.18. The intesting (i) has elongated, and the liver (l) is more prominent. |
| Image Date | 1912 |
| Subject | Northern quahog--Eggs
Northern quahog--reproduction
Northern quahog--Locomotion
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| Image Source Author | Massachusetts. Commissioners on Fisheries and Game. |
| Image Source Title | Report Upon the Quahaug and Oyster Fisheries of Massachusetts |
| Pub. Info. | Boston, MA : Wright & Potter Printing Co., 1912 |
| Page No./Plate No. | Fig. 15-27 |
| Digital collection | Freshwater and Marine Image Bank |
| Repository | Most materials are located in the University of Washington Libraries. Images were scanned by staff of the UW Fisheries-Oceanography Library. |
| Copyright | Materials in the Freshwater and Marine Image Bank are in the public domain. No copyright permissions are needed. Acknowledgement of the Freshwater and Marine Image Bank as a source for borrowed images is requested. |
| Ordering Information | The University of Washington Libraries does not provide reproductions of this image. This record contains a citation for this image. If you want to use the scanned image, acknowledgement of the Freshwater and Marine Image Bank as a source for borrowed images is requested. |
| Type | Image |
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