844 " THETIS " SCIENTIFIC RESUIlTS. 



the neighbourhood of San Die^o to the neighbourhood of Queen* 

 Charlotte Islands on the coast of British Columbia ; and a single- 

 specimen was found at "Albatross" Station 3775, " off Japan." 



THUIARIA SINUOSA, Bale. 



(Plate Ixxxv., fig. 4.) 



Thuiaria sinuosa, Bale, Proc. Linn. Soc. N. S. Wales, (2), iii.,. 

 1888, p. 772, pi. xviii., figs. 9, 10. 



Station 54, 



This species does not seem to have been referred to since Bale 

 published his original desciiption from " a small piece taken 

 from a specimen in the Museum, which is about two inches high, 

 and incomplete." The present specimens give a better idea of 

 the mature growth of the species, for the largest is 125 mm. long, 

 with a straight stem, fascicled to within 25 mm. of the tip, 2 mm. 

 in diameter at the base, and gradually tapering upwards. 

 Although the majority of the colonies are simple, the largest 

 bears, 4 mm. from the base, a strong branch in all respects 

 similar to the stem, while another fragment bears three branches, 

 from one of which spring similar branches of second degree. 



Occasionally, some of the lower pinnae show a special develop- 

 ment, for the hydrothecse disappear, and the central tube is con- 

 tinued as a stolon-like process. The utility of such a develop- 

 ment is manifest where the modified pinnse actually come to- 

 function as stolons which, attached to a substratum, give rise to 

 new and practically independent colonies (PI. Ixxxv., fig. 4). This- 

 phenomenon in I'huiaria sinuosa corresponds to the production 

 of " rameaux stoloniques," a vegetative process adopted as a sub- 

 sidiary mode of reproduction by many Hydroid species. ^^ 



Gonangia are present on several of the colonies. 



Dimensions. — 

 Stem, diameter of cladate tube (including hydrothecse) 0-56 ram. 

 Pinna, length up to 25 



,, diameter (including hydrothecse) 0'46-0-56 



Hydrotheca, length 0-47-0-56 



,, gieatest diameter 0"12-0'15 



Gonangium, length 1"5 



,, greatest diameter 067-0'74 



Locality, — Station 54, within Jervis Bay; depth, 10 toll 

 fathoms; bottom, seaweed and sand; 20th March, 1898, 

 Hitherto recorded only from Port MoUe, Queensland. 



»» See Billard— Ann. Sci. Nat., Zoo!., (8), xx., p. 12, et seq. ' 



