OLIGOCH AETA BAY LIS. 



17 



middle. The second pan' spring from the under side of the dorsal vessel, and join 

 (lie lateral vessels heliind the pharynx, just before they unite into the ventral trunk. 

 Behind these commissural vessels, the dorsal vessel also gives off small branches to 

 the viscera. 



The blood is of a yellow or very pale orange colour in living specimens it 

 may perhaps be red. 



Nervous N//.v/ m. The brain (Fig. 4) is of an oblong shape, but slightly broader 

 posteriorly. Its outline behind is nearly straight (very slightly concave). The brain 

 gives off at its two anterior corners the usual pair of circum-pharyugeal connectives, 

 which join below to form the ventral nerve-cord. The first ventral ganglion appears 

 to send out anteriorly a bundle of nerve-fibres to the body-wall. In other respects 

 there is nothing worthy of remark in the nervous system. 



.\ i'h nil in. These (Fig. ()) are of the type usual in KiK-ln/fni'iix. Only the ciliated 

 funnel projects through the septum into the preceding segment, the main mass of 

 the organ lying horizontally, and its duct to the exterior passing off at a right angle. 



Mdle Gi'iiitnl (.In/an*. The testes are in segment XL on the septum X./XI. 

 The large sperm-sacs (Figs. 1 and 8, SS) occupy segments X. and XL, and in the 

 eleventh there is a pair of large sperm-funnels of an elegant urn-shape, for conveying 

 sperm from the sacs to the exterior. These funnels (Fig. 7) are composed of three 

 parts : the " funnel " proper, being a trumpet-like expanded rim lined with long 

 cilia; a thick-walled portion in which the contents of the cells appear granular and 

 deeply-staining, and a wider portion forming the base of the urn, with walls composed 

 ot tall cells. From the base of this arises a very long and much convoluted sperm- 

 duct (Fig. 8, SD), which finally opens on segment XII. by the conspicuous Heshy 

 protuberances (Fig. 8, $) mentioned among the external features. Just before its 

 external opening (Fig. f>) the duct passes into a small bulbous expansion, and the 

 orifice is surrounded by little groups of glandular cells (" prostate glands "), arranged 

 in transverse rows (Fig. G, Pr.). 



Ft'inuli' (li'iiitnl (>/;/< / 1/.-: The ovaries (Fig. 8, Uv.) are in segment XII. , and give 

 rise to large eggs with a very abundant supply of yolk. 



The oviducts (Fig. 8, ?) are, as in other EuchytrEeids, mere funnel-like out-pushiugs 

 of the septum XII./X1II. to meet the body-wall. The external pores are very 

 minute. 



The spermathecse (Figs. 1 and 10, Sp.) open, as already mentioned, at, or just in 

 front of, the septum IV. /V. They pass, as a pair of rather thick-walled tubes, between 

 the first and second septal glands on either side, and their inner ends open, as is 

 (curiously enough) usual in this family, into the oesophagus (Fig. 10). At about tin- 

 middle of its length each spennatheca becomes somewhat expanded, and its walls, 

 which are ciliated, arc at this point thrown into one or more pockets. Near the 

 external opening the ducts are covered external! v by a few lar^e. stalked ^land-cells 

 (Fig. 10, G.). 



E 



