HYDROIDA II 



65 



mobile sarcothecse. The hydrocladia are divided by transverse nodes into internodia of which normally 

 every second one bears one or two unpaired sarcothecse in the median line, the alternate ones having 

 a small hydrotheca with a snpracalycine pair of sarcothecse at the month, and an unpaired median sar- 

 cotheca on the proximal part of the internodium. The hydrotheca is about \! $ to ' /- the length of the 

 iuternodium, and is on one side entirely fused therewith. 



The gonotheca; are attached by an almost rudimentary stalk to the apophyses; they are oval 

 to pear-shaped, with a distally laterally placed asymmetrical opening. 



200 rn. _. - 600 m looo m. 2000 m. 



Fig. XXXI. The distribution of Nemertesia anUnnina ill the Northern Atlantic. 

 In the hatched parts the literature notes a scattered although common occurrence. 



Material : 



"Ingolf" St. 87, 65°02,3' N., 23°56,2' W.; depth no fathoms 



- 92, 6 4 °44' N., 32 52' W.; 976 



- 98, 6 5 ° 3 8' N., 26°2 7 ' W.; - 138 

 Greenland: Davis Strait, — 80 



6 5 2 7 'N, 54°45'W.; • 67 

 Iceland: 5 miles E. of Seydisfjord, 135 



i,4" 



5,9° 

 (without further details) 



The Faroe Islands: Deep hole at the north point of Nolso, depth 100 fathoms. 



Some luxuriant colonies from Davis Strait exhibit interesting variations in the number of 

 hydrocladia. The nodes of the stem are slightly marked, and each iuternodium bears but three apo- 

 physes; owing to the revolution of the internodia therefore, these colonies or parts of colonies are six- 

 rowed; among these colonies again there are others, or in the single colony, other parts, which in a 



The Ingolf-Expedition. V. -. 9 



