HYDROIDA II 



II 



creeping colonies of La/oca gracillii)ia, and a number of colonies which have later been identified as 

 Lafoea pygmtsa should doubtless be referred to La/oea gracillima. Bonne vie, (1899 p. 62) notes in 

 her table as to the hydrothecfe that they have "slightly outward-curving margin"; this does not agree 

 with Hincks's expression "hydrothecae . . . cylindrical, elongate and narrow" or with his drawing of 

 the species. In my first report on the hydroids from "Michael Sars" (1903 the table) I recorded Lafoea 

 pygnuca from several localities, giving also a drawing of the coppinia of the species; subsequent revi- 

 sion of the material has shown me that the specimen indicated is, like most of the others, a typical, 

 creeping Lafoea gracillima, while some few colonies are creeping Lafoea diiniosa. Lafoea pygvura must 



600m, 



._ 1000 m. 



Fig. II. Localities of Lafoi-'a gyacillinia forma typica • and forma elegantula -f- in the northern Atlantic. 



In the hatched regions the literature denotes a common occurrence of the species. 



(The dates from British seas are incomplete on account of a general confusion with Lafoea fruticosa). 



thus mainly be regarded as .synonymous with Lafoea gracillima and Calycrlla syringa, and can accor- 

 •^ingly no longer be counted as an independent species. 



Lafoea gracilhina appears in two forms, affording parallels to those of the following species. 

 The finely built forma typica is quite cosmopolitan in its occurrence, and has been met with in all 

 seas from pole to pole. In arctic — and as far as can be seen also antarctic — waters, there has also 

 developed, in addition to forma typica^ a more robust and closely built forma elegantula^ the stalk of 

 which generally commences with a single loose winding, continuing then in a varying number of 

 close turns. Forma elegantula is, as mentioned, arctic, but may (text fig. II) also at times penetrate 

 into boreal waters. 



