HYDROIDA II 



93 



region of the warmer seas and the upper abyssal region; quite exceptionally it may penetrate deeper 

 down, as seen from the above. In the boreal regions it is not altogether rare, and has even in a 

 single instance been met with in the cold area. 



. 2 ooo m. 



Fig. L. The distribution of Thecocarpus myriophyllum in the northern Atlantic. 

 In the hatched regions the literature notes a common, although scattered occurrence. 



Gen. Aglaophenia Lamouroux. 



Upright pinnate colonies with branched or unbranched main stem, the apophyses bearing un- 

 branched hydrocladia with several hydrothecse. All sarcothecse immobile. Gonothecae in a corbula 

 formed by a metamorphosed hydrocladitim ; the corbula blades (ribs) are furnished with sarcothecse, 

 but lack hydrothecse. 



Aglaophenia tubulifera Hincks. 



1861 Plumularia ttibulifera, Hincks, A catalogue of the Zoophytes of South Devon, p. 256, pi. 7, 



figs. i2. 

 1868 Aglaophenia tubulifera, Hincks, A history of the British Hydroid Zoophytes, p. 288, pL 63, fig. 2. 



The colonies are pinnate with unbranched or branched monosiphonic main stem divided into 

 short internodia. The internodium has close below the middle an apophyse directed obliquely forward 

 and sideways, and three tubulose sarcothecas, a pair at the upper side of the apophyse and an unpaired 



