250 DISCOVERY REPORTS 



The identification of this specimen with the genus Parapolia rests on the Lineid 

 structure of the proboscis and the absence of head slits. The specific name is taken from 

 Grytviken, the name of the original headquarters of the whaling industry of the South 

 Atlantic, in Cumberland Bay, South Georgia. 



Genus Lineus, Sowerby 



Lineus corrugatus, Mcintosh, 1887 (Plate XVI, figs. 16, 19, 20, 21 ; Figs. 23-27). 



Cerebratithts corrugatus (Mcintosh), Hubrecht, 1887; C. steinini, C. validus, C. subti/is, Burger, 

 1893 ; C. magelhaensicus, Burger, 1895 ; C. Charcoti, Joubin, 1908 ; Lineus autrani, Joubin, 1908. 



Some hundreds of Lineid worms conforming in life to the type L. corrugatus, 

 Mcintosh, were taken from South Georgia and others were collected at stations made 

 off the Falklands and the South Shetland Islands. A great number were examined alive 

 and notes and sketches made of them at the time. A number of methods were used in 

 fixing and preserving them. Identification with the descriptions given by earlier workers 

 has proved a difficult task, and the conclusion I have reached is that there is one species 

 present, widely distributed and very common in this part of the Southern Ocean and as 

 variable in form, colour and size as L. ruber of European waters. 



The following description covers the external appearance of all the specimens in life. 



The length is from a few centimetres to fifty or more at South Georgia. Considerably 

 larger specimens were collected at the South Shetlands. When in motion a 52 cm. worm 

 was 3 mm. across the broadest part of the head; a 17-5 cm. worm was 1-5 mm. across 

 the body. 



The colour varies from light fawn to greyish black through all shades of fawn, light 

 reddish brown, greenish brown, dark red-brown and brownish black. The ventral side 

 is nearly always paler than the dorsal. Two white tags from near the posterior ends of the 

 cephalic slits pass upwards. The incomplete band thus formed is occasionally complete 

 and very rarely double. Sometimes the tags are faintly marked and sometimes they are 

 absent. The tip of the snout is white, and the cephalic slits are lined with white. The 

 white lining may extend the whole length or it may stop at the tags. The body colour 

 usually fades towards the tail. The colour of the head may be slightly greenish and some- 

 times a reddish patch may be apparent on the body just posterior to the head. Occasion- 

 ally there is a trace of a light median line on the snout. The cephalic slits have a white 

 granular appearance inside and a trace of red at the hinder end. Irregular light trans- 

 verse wrinkles are present especially towards the posterior end. 



The body is slightly flattened. The head is distinctly flat and somewhat wedge-shaped. 

 A "neck" is visible when the animal is moving. The mouth is large and no traces can 

 be seen of pigmented eyespots. The darker colours are more general in the smaller 

 worms, and the white tags, besides being very much more evident by contrast, appear to 

 be invariable. 



The specimens in spirit or formalin can be divided into three types : (i) Large pale 

 specimens contracted — often into a spiral with the tail inside — and wrinkled both longi- 



