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II. Note on Piimnoa reseda from the Fccroe Channel, and 

 on its Embryos. By Prolessor J. Arthur Thomson, 

 M.A. [With Two Plates.] 



(Read 26th November 1906.) 



A remarkably fine specimen of Primnna reseda, Pallas, 

 which used to be called the sea-mignonette, was obtained 

 from the Fa^roe Channel (from a depth of 355 metres) in 

 June of this year by the " Goldseeker," one of the vessels 

 engaged in the International Exploration of the North Sea. 

 Through the courtesy of Professor D'Arcy W. Thompson, 

 C.E., I was able to see the splendid specimen a few day.s 

 after capture, when the vessel came into port, and he has 

 also given me permission to make this short note. The 

 species — the only representative of the genus Primnm — 

 has long been known, but an e.xamination of the beautiful 

 specimen in its fresh state has revealed some new facts of 

 interest, e.g., as to the colour and the mode of reproduction. 

 As one of the most gorgeous animals within the British area, 

 it deserves some re-description in English, and a better figure 

 than it has hitherto obtained. 



The .specimen was brought to the surface with its axis 

 caught in a cleft in one of the boards of the trawl, and 

 though without basal attachment, it was otherwise almost 

 undamaged. It is almost a yard in height (34 inches), and 

 its branches spread out for 16 inches. It far surpasses the 

 specimen in the British Museum. 



The axis, where bared at the base, has a diameter of -jVths 

 of an inch, and the average breadth of the branches, includ- 

 ing the covering of polyp-calyces, is fths of an inch. The 

 colour of the colony, which soon began to fade, was a brilliant 

 salmon-pink — a fact which I have not found mentioned in 

 any of the descriptions. Some fragments which I preserved 

 are now creamy white. The bare part of the axis at the 

 base was a tine greenish-bronze, with a metallic lustre. In 

 a class famous for beautiful representatives, Primnoa reseda 

 must be accorded a high place, alike for its graceful branch- 

 ing and for its richness of colouring, not to speak of the 

 elegance of the individual campanulate polyps. In its fresh 



