14 



I'ENNATUUDA. 



Blake, vol. II, p. 142. Bull. Mus. Comp. Zool. vol.15); it seems to be limited essentially to the margins 

 of this part of the Atlantic and to the slope into great depths. As to its bathymetric range 

 the lowest depth is 30 fathoms, at Norway, but upon the whole it occurs in greater depths; on the 

 American side, where, as mentioned, it is very common, it is still found at 1255 fathoms (Verrill: 

 Rep. U. S. Fish. Comm. 18S3 (1885) p. 509), but it is most abundant between 150 and 300 fathoms. 



Whilst the very closely allied Penn. phosphor ea has not yet been found in America, a Penn. 

 americana has been described by Moroff. According to the description, it is beyond all doubt, 

 however, P. aculeata. M.'s specimen is also from Massachusetts (see Zool. Anz. 1902 and Zool. Jb. 

 17. Bd., 1902). 



Pennatula phosphorea L. var. Candida Marsh. & Fowl. 



A. Milnes Marshall and G. H. Fowler: Report on the Pennatulida dredged by H. M. S. : Porcupine». 

 Trans. Roy. Soc. Edinb. vol.23, P ar t 2, 1887, p. 456, PI. XXXI; PL XXXII, Fig. 3. 



This form has been founded by Marshall and Fowler 1. c. on three fragments taken by 

 the «Porcupine» in 1869 at 62 1' N. Lat. 5° 19' W. Long. Our Zoological Museum has obtained 17 

 specimens from the Vestman Islands, 7 from the physician Thorsteinn J 6ns son, who, according 

 to «Skyrsla um hid islenzka nattiirufrseflisfelag arid 1897 — 98', p. 12, has also given a specimen to the 

 Natural History collection at Reykjavik; 8 specimens from the cruise of the «Diana» in 1900 (A. C. 

 Johansen); 1 specimen from 1901 (R. Herring), and 1 from the collection of the «Thor» in 1903. 

 The species is peculiar by its being perfectly white in spirit, almost all the spicules being colourless; 

 the animal, when living, may be of a slight reddish colour (according to Horring), and in a single 

 specimen the red colour is still distinctly seen (see below). Otherwise it agrees in several features 

 with Penn. phosphorea var. angustifolia Koll. (Mouogr. p. 130). The pinnules are slender, and the 

 calices of the polyps are long and conspicuous, provided with 8 long teeth formed by spicules; the 

 number of pinnules 011 either side 17 — 24 (often differing somewhat on the two sides of the rhachis; 

 comp. below). The tentacles of the polyps carry spicules along the dorsal side of the stem. The 

 large spicules, as elsewhere in P. phosphorea, are fusiform, and thus only conspicuously triangular at 

 the ends; in section, they are somewhat round; the smaller ones, on the other hand, are altogether 

 triangular. The largest polyp-spicules measured are ro72 mm long, and o - 072 mm thick; the smallest are 

 0*04 — o-048 mm long, but the general length of the spicules of the tentacles is 0-096 — o-i28 ,nm . 



The specimens in hand show the following particular features: 



