34 



HYDROIDA 



a basal whorl of up to 37 tentacles, which, when extended, attain a length of 40 mm. The distal ten- 

 tacles, when extended, attain a length of 9 mm; they are placed in large numbers round the mouth 

 in a main whorl formed by two or more irregular and closely set circles. 



The gonophores are cryptomedusoid and globular ($) or sub-oval (J 1 ), often somewhat tapering 

 distally, but without any rudiments of tentacles. The gonophores are supported by unbranched and 

 strongly contractile blastostyles, which, when extended, attain a length of 40 mm. The gonophores 

 first ripen at the apex of the blastostyle. As many as 32 blastostyles may occur, but, in general, the 

 number is much smaller; the blastostyles arise close above the basal whorl of tentacles. 



Material: 



"Ingolf" St. 102. 66°23' N., io°26' W., depth 750 fathoms, -~ o°o, C. 



- 107. 6 5 °3 3 ' - io° 2 8' - -492-^ °3 - 



- 139- 6 3°3 6 ' - 7°3°' - — 702 - -=- o°6 - 



Greenland: Godthaab (no particulars) [A 11m an' s original specimen of Monocaulus groenlandica\ 



Davis Strait, depth 100 fathoms [labelled Amalthaea islandica\. 

 Iceland: 66°o2' N., n°o5' W. 



5 miles east of Seydisfjord ; depth 435 fathoms. 



The fairly well preserved specimens of the material recently collected show the following cha- 

 racters (all the measurements are given in mm). 



