56 MR JAMES RITCHIE : SUPPLEMENTARY REPORT ON 



Dimensions of hydrotheca : — 



Length ...... 0-45-0-52 mm. 



Diameter where it becomes free from internode . 0'25-0'27 „ 



Diameter of " neck " ..... Oi4-0-16 „ 



No gonangia were present. 



It is with some doubt that these specimens, their gonangia lacking, have been referred 

 to the S. fusiformis of Hincks. The hydrothecse in our specimens appear to be more 

 robust, to have a more decided " neck," and a more pronounced inclination away from 

 the stem, while the presence of internal teeth is not mentioned in Hincks's description. 

 The present specimens closely approach the very doubtful S. fusiformis (??) described by 

 Professor Cl. Hartlaub (1900, pi. 5, fig. 9) from Rovigno on the Adriatic Sea, but the 

 ringing w^hich is absent in his is markedly present in our examples. 



Locality. — Growing on seaweed found on the shore to the N.E. of Porto Grande, 

 St Vincent, Cape Verde Islands. 1st December 1902. 



Sertidarella gayi (Lamouroux, 1821). 



In addition to the colony found near Gough Island, another of almost equal dimen- 

 sions, 12 cm. high, has to be recorded from St Helena. Its minute structure is very . 

 similar to that of the Gough Island example, the rugosities on the upper surface of the 

 hydrothecse being in some cases almost obsolete. 



This species, although widely distributed in the Northern Atlantic and in the 

 Mediterranean Seas, has hitherto been recorded south of the equator only from the Cape 

 of Good Hope (Algoa Bay), (Hartlaub, 1905, p. 6 I 3). In conjunction with this occur- 

 rence the two Scotia records, from Gough Island and St Helena, may be taken to indicate 

 a wide distribution for the species in the South as well as in the North Atlantic. 



Locality. — Intertwined with an Alcyonarian, Aniphilaphis regularis, from St Helena. 

 30th May 1904. 



Sertularia coriiiciyia (M'Crady, 1859). 



Scanty material, a mere half-dozen colonies, represent this species. The stems arise 

 from a stolon creeping upon the surface of the fragment of Codium also invested by 

 S. rathbuni and S. heterodonta, from the former of which, indeed, they are almost 

 indistinguishable to the unaided eye. The largest is only 6 mm. in height. The 

 specific characters agree with those given by Nutting (1904, p. 58), but the following 

 variations were noted. Tlie stem internodes are proportionally longer than in 

 Nutting's specimens, for while in his examples the " height of the hydrothecae is 

 usually about equal to that portion of an internode which lies between the hydrothecal 

 base and the node below," in ours the latter distance considerably exceeds the former. 

 Our hydrothecse, again, have a longer distal portion free from the stem, the result being 

 that the proportion of the anterior adnate part to the whole length of the hydrotheca is 



(rot. soc. edin. trans., vol. xlvii., 78.) 



