430 Hjalmar Ditlevsen. A marine Dorylaimus from Greenland waters. 



the tail. The greatest thickness is measured near the vulva, a little 

 before the middle of the animal. The front end is marked by a 

 rather sharp constriction. The mouth is surrounded by 6 prominent, 

 nearly globular lips devoid of papillæ. The tail is tolerably short, 

 conical with hook-shaped tip. This hook-shaped tip is present in 

 all the specimens even when the whole body for the rest is stretched 

 out. The spear of the mouth is strong, measures с \1 ц in length 

 and is of the well-known, usual quill-shape with its apex obliquely 

 cut off. 



The oesophagus, the length of which measures between ^/s and 

 Vß of the length of the whole animal, has its greatest thickness in its 

 proximal end and tapers evenly towards the front end of the animal. 

 The nerve-ring is seen on the limit between the first and second 

 third of the oesophagus. 



The intestine has its hindmost part differentiated in the same 

 way as usually occurs in this genus and is seen under high magni- 

 fying powers to contain dark refractive granules. 



The reproductive organs stretch only slightly forward and back- 

 ward in the animal. The down-bent terminations of the ovaries pass 

 each other with their tips respectively from behind and from before 

 exactly over the vulva (see fig. 1). Only one of the individuals had 

 ripe eggs; they are found to the number of two, one before and one 

 behind the vulva and are rather thick-shelled. They measure 82 /^ 

 in length and 32// in breadth. 



Finally I shall only point out, that while the Dorylaimus 

 marinus Dujardin must be arranged in the group s of de Man to 

 which belong Dorylaimus stagnalis, brigdammensis and others, the 

 species here dealt with must be arranged under the group y for which 

 D. Carter! is the main type \ 



Measurement of adult female with shell-eggs: 



Length 2'46 mm. 



Breadth O'OO? — 



Vulva 1-18 — 



Oesophagus 0*04 — 



Tail 0.01 — 



^ De Man : Die frei in der reinen Erde und im süssen Wasser lebenden Nematoden 

 d. Nieder!. Fauna. Leiden 1884. 



