24 
an adhesive fluid which during the copulation serves for fixing the 
male bursal region to the body of the female. The feature would 
thus — according to my opinion — be analogous to what is known 
in certain insects as copulation-markings, viz. 
the Dytisci. The female organs are symmetrical 
and the ovaries are reflexed. Only two eggs 
are found in each uterus-branch of the females 
at my disposal. The hindpart of the male is 
bent inwards in this and related forms. In the 
mid-line, ventrally, a papilla is situated with 
the opening for the giand which Jagerskiold 
has named „accessorische Driise“ and which, 
according to the same author, serves as an or¬ 
gan of fixation during the copulation. I think 
that this organ, in spite of its somewhat dif- 
ferent structure, is to be considered as homolog- 
ous to what is commonly called the supplement- 
ary organ in the Enoploids and other genera 
of freeliving Nematodes. Besides the supple- 
mentary organ a subventral row of large mam- 
ma-shaped papillæ is found in this species on 
each side, each row counting five papillæ. 
These “bursal papillæ“ are found in most of 
the Thoracostomes belonging to this group; 
T. papillosum also described in this paper, 
and de Man States their presence in T. setosum as well as in 
T. antarcticum. The spicules are rather short and thick, and on 
their ventral edge a rather thin crest is seen. They are provided 
with a thickening-list in the middle. From the proximal end to the 
distal tip is a length of 200 p. A rather large accessory piece 
embraces their distal ends and is provided with a backwards point- 
ing, somewhat curved apophyse. 
Thoracostoma papillosum n. sp. 
PI. I fig. 12. PI. II, ligs. 9. 12. PI. III, figs 6, 8, 10. 
Locality : Campbell Island. Perseverance harbour. The coast 
at ebb-tide; under stones. 
Length: Female 21,8 mm. Male 18,7 mm. 
Fig. 16. Thoracostoma 
campbelli; spicular 
apparatus. 
they are found in 
