GALATHEALINUM BRACHIOSUM 



413 



I have had no complete tubes of G. brachiosum at 

 my disposal. The longest fragment of tube, the one 

 which contained the animal, was 238 mm long. At 

 its front end the diameter was 2-6 mm and at its 

 hind end 2-0 mm. 



Galathealinum brachiosum is distinguished from 

 G. bruuni by the much greater number of tentacles, 

 the shape of the cephalic lobe, the larger cuticular 

 plaques and the greater number of them on each 

 papilla. The body of G. brachiosum, moreover, is 

 considerably larger. As regards the number of 

 pairs of metameric papillae in G. bruuni, we must 

 rely on Kirkegaard's (1956) drawing (reproduced 

 here as Fig. 161). He has illustrated only a small 

 fraction of the metameric region of the trunk, but 

 this includes no less than thirty pairs of papillae 

 and the total number must be much greater. G. 

 brachiosum has only 24—27 pairs. The papillae of 

 G. bruuni also seem to be much smaller than those 

 of G. brachiosum. It seems clear that G. brachiosum 

 has fewer but larger papillae than G. bruuni. 



The differences between the species are laid out 

 in Table A5. 



Fig. El 62. Galathealinum 

 brachiosum: part of the 

 tube. (After Ivanov 



1961c) 



Fig. F162. The felt-like structure of the funnel-like frills of the tube in two species of Galathealinum 



at the same magnification. 



A-G. brachiosum; В -G. bruuni. (After Ivanov 1961c.) 



