284 ERNEST WAEEEN. 



The variety coopein has typically two alternating whorls 

 of four capitate tentacles ; but it exhibits marked variability 

 in this character, and most of the arrangements above men- 

 tioned, as typical for the different species, occasionally occur 

 in it. The matter has been discussed in the ' Ann. Nat. Grov. 

 Mus.,' vol. i, p. 209. 



From these considerations it would ap]3ear to be more 

 satisfactory to regard the Natal hydroid as a variety, or per- 

 haps as an incipient species, oi'iginating from P. australis. 



(8) Cladocoryne floccosa Botch. 



Cladocoryne floccosa Botch. ' Ann. Nat. Hist.,' March, 1871. 



This unique hydroid with capitate pinnate tentacles was 

 found originally at Herm, near Gruernsey, and has been 

 described and figured in AUman's monograph. I am not 

 aware that the hydroid has been met with elsewhere ; but it 

 was found fairly abundantly at Isipingo and Scottburgh in 

 the month of May, 1907. It occurred in rock-pools, and 

 especially on old polychast worm-tubes which had become 

 covered with sea-weeds and poly/.oa. 



The colony consists of a running stolon which gives off 

 short upright stems, from one quarter to half an inch high, 

 which generally carry a single terminal polyp. Occasionally 

 the stem may give off a short lateral branch. 



The following measurements of an average preserved speci- 

 men are giveu, in order that a comparison may be made with 

 the European hydi*oid. 



Hydrorhiza; diameter 0' 182 mm, thickness of perisarc 

 155 fj. 



Hydrocaulus; diameter 0*152 mm., thickness of perisarc 

 8-9 fi. 



Hydranth; total height about 0'9 mm., breadth about 



0"5 mm. Diameter of capitulum of tentacle about 0"058 mm. 



Nematocysts are at least of two kinds : the large measure 



iri /x in length and 9'0 fx in breadth, and the small, 6*7 ft 



and 5'o ju respectively. 



