8 MM. Kowalevsky and Barrois on Anchinia. 
Ascidia. Finally the whole of the digestive tube is sur- 
rounded by a network of cells (7), which may be regarded as 
the kidney. 
eg. Generative organs.—The genital glands are situated in 
the space included between the pharyngeal sac and the cloaca, 
and in the lower part of this space; they are placed to the 
right of the intestine, between it and the cloacal expansion of 
the right side; and both open by a common aperture (oc) at 
the lower part of this cloacal expansion. The mature testis 
(¢) consists of a narrow deferent duct and of a voluminous 
ramified gland, partly concealed by the branchia, and which 
clothes the whole anterior portion of the intestine. ‘The ovary 
consists of a common wall (0) which contains ova (ov) at diffe- 
rent stages. The oldest ova are situated at the extremity of 
the sac on the side opposite to the aperture ; then follow two 
or three ova less and less developed, and finally a small 
mass of indifferent cells which are placed quite close to the 
aperture. 
h. Endostyle-—The very short endostyle presents in trans- 
verse sections the structure shown in fig. 10. It is composed 
of two symmetrical halves, separated by a very deep groove 
in the buds. Below this groove there is on each side a narrow 
cell furnished with a very long cilium, which projects out of 
the cavity of the endostyle. ‘Then comes a zone of radiating 
cells, at the inner angle of which is seen a small, rounded, and 
very strongly coloured cell. The radiating zone is succeeded 
by asecond zone, to which carmine attaches itself preferently ; 
it consists of cells with large nuclei, with no great amount of 
protoplasm, which alternate more or less, and are not, like the 
preceding, arranged in a single row. Lastly, this second zone 
is surmounted by a large clear cell, which bears at its inner 
angle a rounded and very strongly coloured cell. This last 
bounds the aperture of the endostyle. The whole inner sur- 
face of this organ seemed to be furnished with fine cilia. 
It is at the inner angle of the coloured cell that is inserted 
the wall of the pharyngeal sac, which commences with a cell 
larger than the others, and the existence of which appears to 
be constant (fig. 10). From this point the wall acquires its 
definitive structure, formed of long flattened cells. Neverthe- 
less we do not see it immediately take a direction to the right 
and left to form the lateral parts of the pharyngeal sac. In 
fact it begins by rising upwards, and then bends round, 
forming a small loop occupied by a few thicker small cells ; 
these last are nothing but the section of the vibratile line of 
each side; and we see therefore that this line, in the part of 
it which is horizontal and parallel to the endostyle, is not 
