Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0101clau Year: 1884 THORACOSTRACA. 465 The ducts of the very numerous, multilobed hepatic c-eca open into the anterior part of the elongated intestine. A simple or looped glandular tube (the green gland} opens on the basal joint of the posterior antenna. A shell gland is not developed. The nervous system is distinguished by the size of the brain, which is placed far forwards and gives off nerves to the eyes and antennae. The ventral cord, which is connected with the supra- cesophageal ganglion (brain) by ve
Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0101clau Year: 1884 THORACOSTRACA. 465 The ducts of the very numerous, multilobed hepatic c-eca open into the anterior part of the elongated intestine. A simple or looped glandular tube (the green gland} opens on the basal joint of the posterior antenna. A shell gland is not developed. The nervous system is distinguished by the size of the brain, which is placed far forwards and gives off nerves to the eyes and antennae. The ventral cord, which is connected with the supra- cesophageal ganglion (brain) by very long commissures, presents very different degrees of concentration. In the brachyurous Decapods this concentration reaches its highest point, all the ganglia being together to form one great thoracic ganglionic mass. The system of visceral nerves is also very highly developed. Sense organs.—The eyes are large and facetted. Except in the
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