4 8 



HYDROIDA II 



Greenland: Snkkertoppen, on Bol tenia (without further details). 

 Iceland: Brunnes, depth 4 fathoms 

 Seydisfjord — 6 — 

 Hvalfjord — 46 metres 

 Stykkisholm — 30 fathoms. 

 The Faroe Islands: 6 miles N. by W. of Store Kalso, depth 60 fathoms 

 Deep hole at north point of Nolso — 100 — 

 Glyversnaes near Thorshavn, on red algte. 



There may be some possibility that the colony here 

 shown (fig. XX) from the "Ingolf" St. 87 does not altogether 

 agree with Halcciiini tenellum. On comparing with the des- 

 criptions given by Hincks (1868 p. 226, pi. 45, fig. la), Rit- 

 chie (1907 p. 525), and Jaderholm (1909 p. 14) the gono- 

 theca? do not agree with those shown. Hincks describes 

 them as follows: "the capsules vary in form, being broadly 

 ovate, or slender and somewhat pointed above; they contain 

 a single, large gonophore". His figure shows us a slenderly 

 oval or more pear-shaped gonotheca broadly rounded at the 

 distal end. Ritchie's description is as follows: "The gou- 

 angia are ovate, broad in the proximal region, obtusely pointed 

 in the distal. They are supported on short stalks, which arise 

 from the sides of the hydrotheca, and always from the lowest 

 segment in any hydrotheca tier". Jaderholm writes: "Go- 

 notheken eirund, unter den Hydrotheken ausgehend und (nach 

 Thornely) audi von der Hydrorhiza und aus der Hydro- 

 thekenmunduug. Distale Zahne fehlen". From the statements 

 here quoted, it is not easy to gain a clear impression of the 

 gonangia, and none of them will altogether cover the present fertile colonies, of which there are 

 not a few in my material, and which agree with the specimen shown. 



The gonotheca; are here set on short stalks, close under the primary hydrothecae, or may 

 exceptionally arise from the interior of the same; this agrees with the statements given above, 

 as also with a later observation by Ritchie (191 1 p. 30) where however, nothing new is stated as to 

 their shape. The gonotheca contains, as Hincks points out, a single large gonophore, but the state 

 of preservation of the material did not permit further investigation of this. On the other hand, the 

 shape of the gonotheca agrees but ill with Hincks's drawing, and forms rather a cross between 

 the description given by Ritchie and that of Jaderholm, not improbably because the gonothecse 

 are somewhat flattened. In lateral view, they are egg-shaped, with a broad basal part, and pointed 

 distal end; viewed from the flat, on the other hand, they are more elongated oval, more or less trans- 

 versely cut off at the distal end. On comparing this with the passage from Hincks's description 

 quoted above, we find that his expression "broadly ovate, or somewhat pointed above" agrees after 



Bv 



Fig. XX. Halecium tenellum. 

 9 from "Ingolf St. 87. 

 a gonotheca formed as heterorenovate. 

 (X 20). 



