NORTH AMERICAN ALCYONARIA. 543 



Two of these six species belong to genera [Faragoryia and 

 Primnoa) that do not occur in Kiikenthal's list. As regards the 

 Sea-pen, Osteocella septentrionalis (Hickson, 1911), it may be a 

 matter of controversy whether we are justified in separating the 

 species from the genus Pavonaria, of which two species {P. cali- 

 fornica and P. loillemoesi) have been described from Californian 

 waters, but there seems to be little doubt that the species is quite 

 distinct. 



Glavularia inoresbii is closely related to, but quite distinct 

 from, the C. pacijiaa of Californian waters. The genus Clavidaria, 

 however, being cosmopolitan in distribution and having many 

 very variable species, does not afford much assistance in the 

 determiiiation of marine zoological regions. 



The genus P^ammogorgia, on the other hand, appears to have 

 principally a tropical and temperate distribution, and the occur- 

 rence of one species north of the Straits of Fuca may be regarded 

 as an example of the fauna of the southern subregion over- 

 lapping the boundary-line. Three species of this genus have 

 been described by Nutting from Californian waters, but I have 

 found the determination of species of Psammogorgia, without the 

 examination of type-specimens, so extremely difficult that I feel 

 great hesitation in my identification of the Vancouver specimen 

 as Ps. teres and can make no further comments upon it. 



The genus Caligorgia has many species in the Pacific Ocean, 

 but according to Versluys (1906, p. 169) it is unknown in the 

 North Atlantic. The species found oft' the coast of California 

 (C. kinoshitcB), however, is quite distinct from the species 

 described in this paper from the Gulf of Alaska. 



The occurrence of a specimen of Stylaster in the Vancouver 

 seas is of interest, because it belongs to the same form or sub- 

 genus (AUopora) that occurs in the Norwegian fjords, and not to 

 the form or subgenus {Stylaster) which is so connnon in tropical 

 and subtropical waters. It has been previously described by 

 Verrill from the coast of California, but is probably a migrant 

 from the north. 



To summarise the results, it may be. said that in this small 

 collection three species at least {Stylaster norvegicus, Paragorgia 

 arhorea, and Primnoa loilleyi) are representatives of a circumpolar 

 fauna, one {Psammogorgia teres) is a, representative of the south 

 coast fauna, and the other three {Clavularia inoresbii, Caligorgia 

 fraseri, and Osteocella septentrionalis) may represent a common 

 Pacific element which extends both north and south of the line 

 between the two subregions. 



A comparison of the list of species described in this paper with 

 Kiikenthal's list of Californian species shows that not a single 

 species of Alcyonaria (except possibly the Psammogorgia) has 

 been found both north and south of the Straits of Fuca, and 

 seems therefore to justify a division of the Oregonian region at 

 that point into two subregions. The specimens I have been 

 able to collect together may represent only a small fraction of the 



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