1910.] Frtojf CHRISTMAS island. 831 



but I liave hoon guided by tlie very siu.-dl diuiensious of those 

 specimens, wliicli ai-e even less tliiui those of specimens recorded 

 by Pictet from Aiiiboyuii*, and by YanhoHen from the Houth 

 Atlantict, and approach most closely in size tlie original speci- 

 mens of CamjKiii.ular'ta attenaata Calkins, I'egarded by Vanhullbu 

 (I.e.) as identical with Clyiia vollfonais. 

 Dimensions : — • 



Total length 1 -5-2 5 mm. 



Stem, diameter 0"054-(J-n66 mm. 



Hydrotheca, depth 0"32-0'45 mm. 



,, diameter at mouth ...... 0"21-0'28 mm. 



Locality. Flying- Fish Cove. 



This species has not hitherto been recorded from the Indian 

 Ocean. 



Clyiia serrulata Bale. 



1888. Camjmnularia ? serruloM Bale, Proc. Linn. Soc. N. )S. 

 Wales (2), vol. iii. p. 757, pi. xii. tig. 4. 



A single poor colony, growing along with Plibmidaria setacea 

 Linn., the structures and dimensions of whicli agree with those 

 given by authors. 



Loccd'dy. Flying- Fish Cove. 



This species has not hitherto been recorded from the Indian 

 Ocean, although VanhofFen has recently desci'ibed specimens i\:o\\\ 

 Observatory Bay, KerguelenJ. 



Family 8 e r x u l A r i d /E. 



Sertularella polyzoxias Linn. 



1758. Sertidavia polyzomas Linnajus, Sj'st. Nat., ed. x. p. 813. 



A solitary coUmy was found on the stem of Pennaria disticha, var. 

 austrcdis. Although its structures appear to be indistinguishable 

 from those of S. ]iolyzoiiias, this specimen is exceedingly minxite, 

 only 3 mm. lu'gli, reminding one of the small New Zealand 

 variety figured by Hilgendorf § ; and the dimensions of the hydi'O- 

 theciB are also very much smaller than those of typical specimens. 

 The hydranth has about twelve tentacles. 

 Dimensions : — 



Internode, length ■28-0-35 una 



,, diameter 0'()8 mm. 



Hydrotheca, length 0'28-031 mm 



„ length free O'l 6-0-1 8 mm. 



,, diameter at mouth O'lS mm. 



Locality. Flying- Fish Cove. 



* Pictet, Rev. Suisse de Ziwl., vol. i. 1893, p. 31. 



t V;iiilii">ffen, op. cit. p. '2'.)',t. 



X Viuiliotleii, oj). cit. p. ."302. 



§ Hilgendoi'f, Trans. New Zeal. Inst. vol. xxx. 1898, pi. xx. fig. 2 a. 



