Plate IV. 



Fig. I. Vertical section, along the transversal plane, through a grown specimen, ^^/i. The section is 

 not median. The figure shows the four genital organs of the same side, the two median 

 ones showing the arrangement of the ovary and testis, the ovary medially, the testis later- 

 ally placed. Below the outer genital organ is seen the tentacle-basis. The strongly folded 

 lower side of the section represents the stomodseal folds. On the left side is seen the con- 

 nection between the "chimney" cavity and the "suboral" cavity. The clear spaces below the 

 genital organs and especially in the outer part to the right are sections through the branching 

 peripheral canals. 



— 2—4. Successive horizontal sections through the upper (apical) part of a grown specimen, '^/i- 

 In fig. 2 the section goes through the apical organ, in fig. 3 through the transverse main 

 (perradial) canal, in fig. 4 through the upper part of the oesophagus. The designations excr. c. 

 and s. in figs. 2—3 are not correctly placed. The small pearshaped body seen in the middle 

 of the upper side in fig. 2 is the apical organ, which has become oblique through the 

 contraction of the animal; the small ring below the apical organ is the excretory canal. 

 The space in the middle of the figure is part of the gastrovascular system, as is also the 

 space designated excr. c. in fig. 3. The two darker bodies in the middle of this figure, desig- 

 nated s (apical organ), likewise belong to the gastrovascular system (probably from the inner 

 end of the oesophagus). — Otherwise the figures show the arrangement of the 4 pairs of 

 genital organs, the ovaries being placed subsagittally and subtransversally, the testes inter- 

 radially, after the usual ctenophoran type. The left subsagittal organ on the lower side 

 apparently affords an exception, the ovary being interradial, the testis subsagittal. This is, 

 however, an abnormality, due to a revolution, perhaps the result of the egg-formation. As 

 seen from fig. 2, part of the ovary is in the normal place. In fig. 3 is seen the connection 

 between the transverse canal and the cavity of the right subsagittal genital organ of the 

 lower side; in fig. 4 is seen the connection between the transverse canal and the cavity 

 of the tentacle basis. The sections do not cut the genital organs at the same level, owing 

 to the contraction of the animal which has made it impossible to get perfectly horizontal 

 sections through the whole of the organ.?. Also the tentacle basis to the left is seen (Fig. 4) 

 to have l^een cut obliquely. 



