PLATE XVI. 



Fig. 66. — Cross section through the middle of Van der Hoeven's organ. ('. L. X 8. 



I>. dorsal surface. 



A. atrium. 



G, G, G, glandular portions of the organ. 



(in, ganglion. 



HF, horizontal fissure. 



L, lamina. 



N, nerves to the lamina-. 



SI 1. wall of the atrium. 



VK. vertical fissure. 

 Fig. 67. — Longitudinal section of a gland of Van der Hoeven's organ. C. L. ■ 35. 



18. — Cross section of gland tubules of Van der Hoeven's organ. C. L. ■ 35. 

 Fig. 69. — Section of the mantle through the bases of the preanal papilla?. (.'. L. X 1-. 



< i, (•. glands. 



IM, inner surface of mantle. 



( >, opening of gland. 



OM, outer surface of mantle. 



I'. I'. bases of the preanal papilla;. 

 Fig. 70. Cross section of the salivary gland. C. L. X 20. 



A. artery. 



I'.S. blood sinus of salivary process. 



Y uerve. 



< >, opening from the central cavity of the gland to the pharyngeal cavity. 

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