RINGED-WORMS. FUE 
dividing it, as it were, into cells. Two conical yellow ccecal pouches 
are placed at the commencement of this portion of intestine: they 
may probably be considered to be rudiments of the liver. In 
the common Leech, the short cesophagus, of an oval form, wider 
towards the middle of its length, passes into a long stomach, which 
is divided by transverse walls into eleven portions: on each side are 
seen ten coecal appendages to the stomach, the last of these being 
the longest ; the inferior opening of the stomach (Pylorus) extends, ~ 
like a funnel, into the intestine by a narrow opening. In other 
genera of Hirudinea, ex. gr. in Hamopsis, the intestinal canal is 
more simple, having only two cecal appendages! In Aphrodita 
there succeeds to a very muscular cylindrical tube, which PALLAs 
described as stomach, a thin intestinal canal of considerable width 
with about twenty ccecal appendages on each side?. These append- 
ages are narrow at their insertion into the intestine, wider in their 
middle, where they are provided with branched lappets, and termi- 
nate in longish ccecal sacs. This structure recalls the disposition 
of the intestinal canal in Planarie and Distomata, and the blind 
branched appendages of the intestinal canal in Star-fishes may be 
compared with it. They are filled, as these are, with yellow fluid, 
and may be compared to rudiments of liver. In other animals again 
the liver appears as a protrusion of the intestinal canal. 
The system of Blood-vessels presents very many modifications 
in this class. As to the blood itself, we have seen above, that 
Cuvier believed it to be red in all the ringed-worms. Such is 
really the case in by far the greater number, as Hirudo, Lumbricus, 
Arenicola, Nereis, Terebella, Serpula, &c.: in others it is nearly 
colourless, as in Aphrodite: yellow, as in Polynoé and Phyllodoce, or 
even green, as MILNE Epwarps found it in a species of Sabella. The 
general arrangement of the circulating apparatus is as follows: there 
are two main stems, one on the dorsal surface, the other on the 
ventral surface, which run in the midst through the whole length 
of the body, and as far as the course of the blood could be deter- 
mined in the living body—(for which investigation small indivi- 
duals are frequently more fitted than large ones, on account of their 
1 See a figure in Branpr und Rarzepurc, Medizinische Zoologie, 1. Bd. 1833, 
Tab. xxrx. B. fig. 12. 
2 Paws, 1. 1. Tab. vir. fig. rod, d, fig. 119,g. G. R. TRevIRANUvS in Zeitschrift 
fiir Physiologie 11. 1829, 8. 159—161, Tab. x11. fig. 9. 
14—2 
