424 . SIR WILLIAM TURNER 
axis, and thence into the branches. In transverse sections through the bristles the | 
pigmented core was frequently partially or wholly divided into two portions, which 
were either close together, or were partially fused and formed a dumbbell-like figure. 
REPRODUCTIVE ORGANS. 
Koren and DANIELSSEN, in their account of Pennella balenoptere, figured a dis- 
section of the genito-abdominal segment. They described as present in it a pair of 
ovaries with oviducts, a pair of cement glands with excretion canals, the latter of 
which were nearer to the ventral surface than the oviducts, and two short canals. No ; 
mention is made of the receptacula, and the ova strings were wanting in most of 
their specimens. 
Ovaries.—The ovaries were situated in the upper part of the genito-abdominal 
segment. At and near its junction with the thoracic segment, where the alimentary 
canal was dilated, and the dorsal and ventral spaces were relatively small, short lengths 
of a divided tube were seen in transverse sections to occupy a relatively large region on 
each side of the canal, dorsal to the lateral mesentery, and laterally to the dorsal space ; 
the portions of each tube were scattered in the region, and were, I believe, the upper end 
of the ovary, for they were occupied by nucleated cells which resembled rudimentary 
ova. The oviducts and cement ducts were not present (fig. 17). 
In sections a little lower down the parts of the divided ovary were in greater lengths 
and more continuous with each other, the tube was cylindriform in shape, and had 
reached or almost reached the mesial plane of the parasite, so as to lie immediately 
internal and parallel to the pigmented lining of the chitinous wall, but separated from 
the alimentary canal by the dorsal space. The part of each tube which lay next the 
wall followed its curvature. Somewhat lower down the wall of the tube next to the 
dorsal space bulged into diverticula and lost its cylindriform character. Whilst each 
ovary was in many sections situated entirely on its own side of the mesial plane of the 
parasite, in others the inner ends of the tubes from the opposite sides crossed the mesial 
plane and slightly overlapped each other. In all these sections the oviducts and cement 
ducts were present and were transversely divided (figs. 20, 21). 
The wall of the tube was formed of a delicate membrane, and the lumen contained un- 
fertilised ova (fig. 24). In many instances they were so closely packed together that the 
outlines of the individual cells were obscure. The ova were larger and more precisely 
differentiated when in proximity to the wall of the tube, which, from its surface being 
slightly crenulated, and from the passage of slender processes from the membranous: 
wall into the lumen, seemed to be partially divided into compartments, in each of 
which an ovum was lodged. Each ovum contained a relatively large, well-defined 
germinal vesicle, situated at or near the centre of the cell-plasm, and in each vesicle, 
about its centre, was at least one germinal spot; not unfrequently two spots were 
present, and in some instances I saw three spots in a germinal vesicle. 
