216 PHYLUM ANNELIDA. 
detected in the gut, a diastatic ferment turning the starchy food into 
sugars, and others—peptic and tryptic—not less important. The wall 
of the stomach-intestine from without inwards, as may be traced in 
sections, is made up of pigmented peritoneum, muscles, capillaries, 
and an internal ciliated epithelium. In the other parts of the gut the 
innermost lining is not ciliated, but covered with a cuticle. 
Vascular system.—The fluid of the blood is coloured 
red with hemoglobin, and contains small corpuscles. Along 
1) 
WH ey 
oR hel 
eX Ex, 
Ss 
ae 
Ail 
CA 
es 
WED 
FiG. 112,—Transverse section of earthworm. 
A., Cuticle; B., epidermis; C.JZ., circular muscles; 2.1, longitudinal 
muscles ; D., aseta; C., coelom;_¥C., yellow cells; F., typhlosole ; 
V.V., supra-neural blood vessel; S./., sub-neural vessel ; D.V., dorsal 
vessel; /., peritoneum; £., cavity of gut; G, endodermic lining of gut; 
WV., part of a nephridium ; &., opening of a ne hridium ; 7., the nerve- 
cord; /., a nerve given off; ., giant fibres in the nerve-cord. 
the median dorsal line of the gut a prominent blood vessel 
extends, another (supra-neural) runs along the upper surface 
of the nerve-cord, another (infra-neural) along the under 
surface, while two small latero-neurals pass along each side 
of this same cord. All these longitudinal vessels, of which 
the first three are most important, are parallel with one 
another ; the first three meet in an anterior network on the 
