38 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 4 



Obelia obtusldens (Jaderholm) 

 Plate 9, Fig. 41 



Carnpanularia obtusldens Jaderholm, Hyd. aus den Kiisten von Chile, 



1904, p. 2. 



Trophosome. — Colony simple, reaching a height of 3 cm. Stem 

 slightly geniculate; in larger colonies there are regularly alternating 

 branches, in smaller colonies there may be none. Stem quite extensively 

 annulated in the proximal portion of each internode; short pedicels 

 annulated throughout, longer ones, in proximal and distal portions. 

 Hydrothecae broadly campanulate, almost as broad as long; margin 

 with 12 low, rounded teeth; lines pass backward along the hydrothecae 

 from the indentations. 



Gonosome. — (Not previously described.) Gonangium arising di- 

 rectly from the stolon, with a short pedicel, not annulated, smooth, 

 broad at the distal end and tapering rather rapidly at the proximal end. 

 There is a distinct collar. Length 0.75 mm., greatest breadth 0.2 mm. 



Distribution. — Santa Elena Bay, 10-12 fathoms. 



Obelia plicata Hincks 



Obelia plicata Hincks, Br. Hyd. Zoophytes, 1868, p. 154. 



Fraser, Hyd. of Vancouver Island, 1914, p. 154. 



Distribution. — South of Clarion Island, 50 fathoms; James Bay, 

 50-70 fathoms ; Cartago Bay, 32 fathoms ; between Charles and Inde- 

 fatigable islands, 60 fathoms; La Plata Island, 45-55 fathoms; Gorgona 

 Island, 20 and 150 fathoms; Port Utria, 40 fathoms; Jicaron Island, 

 25-30 fathoms; Pacora Island, 15-25 fathoms; Santa Maria Bay, 35-40 

 fathoms. 



Obelia tenuis, new species 

 Plate 9, Fig. 42 



Trophosome. — Colony small ; sometimes there is a single hydrotheca 

 and pedicel but usually there is a short geniculate stem, giving off up 

 to four hydrothecae in which case it may reach a height of 2 mm. The 

 hydrotheca is borne on a short, annulated, or partly annulated pedicel 

 (the internodes of the stem are annulated toward the proximal end) ; 

 it appears to be an elongation of the pedicel, broadening gradually but 

 not extensively to the margin; the margin has 8 rounded teeth; defi- 



