810 MR. .T. lUTCIlIE ON IIYDUOIDS [May 24, 



Localities. St. 1, east of Tavoy Island and Port Owen, 4 12 

 fathoms, sand and broken shells, and mud ; rare. St. 25, Five 

 Islands, 8 to 12 fathoms, rock and sand, and mud; rare. St. 35, 

 between Warden Island, Howe Island, and Lyall Island, 15 to 2U 

 fathoms, rock and sand ; rare. 



Except from St. 23, where this species also occurs on Sertularella 

 qiiadrideiis, specimens are confined to Idia pristit>. 



From each of Stations 1 and 28 comes a solitary simply-stalked 

 hydrotheca with cone-shaped basal portion, surmounted by almost 

 cylindrical walls terminating in seven or eight sharp teeth. The 

 structure of the basal portion I'esembles that of the hydiotheca of 

 Obelia andersoni Hincks, but I regard the pi'esent specimens as 

 al)normally developed examples of C. raridentata. 



Heuella calcauata a. Agassiz, 18(55. 



One of the most widely distributed of the species in the collec- 

 tion, occurring at eight of the fourteen stations from winch 

 Hydroids were obtained. It shows considerable diversity of 

 form, being usually represented by the long smooth hydrotheca^ of 

 the typical form, but frequently assuming the shape of the variety 

 recorded by Marktanner (1890) as Lafum contorta. This epizoii; 

 species, like several others, shows a remarkable constancy of 

 preference for Idia p7'istis, seeing tliat at all stations, with the 

 exception of Station 9, where it was creeping on Thyroscyjihus 

 viliensis, it occurred on that species, and on it alone. 



Localities. St. 1, east of Tavoy Island and Port Owen, 4 to 12 

 fathoms, sand and broken shells, and mud ; not common, often 

 var. contorta. St. 9, between Bentinck Island and Courts Island, 

 12 to 26 fathoms, sand and shells. St. 14, Bush by Island 

 pearling-ground, shore to 21 fathoms, sand and mud ; i-are. 

 8tt 15 and 16, Ravenshaw Island, Sir John Malcolm Island, and 

 Alligator Rock, 5 to 18 fathoms, rock and sand, or rock and mud ; 

 occasionally present, often assuming the shape of var. contorta. 

 St. 23, Five Islands, 8 to 12 fathoms, rock and sand, and mud ; 

 veiy common, mostly var. contorta. St. 25, Gregory Group and 

 Crichton Island, 4 to 14 fathoms, stones and broken shells, an<l 

 rock ; very rare. Moskos Islands, 3 to 26 fatluinis, rock and 

 sand, or rock and mud ; common. 



HeBELLA CRATEROIDES Ritchie, 1909 /a 



The hydrothecre are smaller than those of the type specimens 

 from the Andaman Islands. Tho liydr.intlis are dei'aycd, ;ind no 

 gonosome was observed. 

 Dimensions : — 



Hydrotheca, depth 0*20 nun. 



., diameter at mouth ()-15-0-17 mm. 



Locnlitie.H. Stt. 15 jind 16, Ravenshaw lsl:ind, Sir John ]\Ialcolm 

 TsImiuI. and Alligator Rock. 5 to 18 fatlumis, i-o,'k :iud sand, or 

 j-ock and mud ; rare, on J.ytocarjnif! plnviiicpus. 



