NO. 28 NKW HYDROIDS FRASER 7 



margin is curved like the margin of a pitcher, and there is a slightly 

 curved, sharp, median tooth. There are six or seven septal ridges 

 between the base of the hydrotheca and the base of the supracalycine 

 nematophores ; there are numerous nematophores arranged on the 

 portion of the main stem that is free of hydrocladia, one in the axil 

 of each hydrocladium and three others between this and the base of 

 the next hydrocladium. On the hydrocladia! internode, there is a 

 median nematophore at the base of the hydrotheca, but free from it, 

 two large supracalycine nematophores and one median near the distal 

 end of the internode. 



Gonosome. — Not observed. 



Holotype.— U.S.N. M. no. 43293. 



Distribution.— North of Puerto Rico, lat. i8°33'i5" N., long. 65° 

 56'45" W. ; 240 fathoms. 



EXPLANATION OF PLATES 



(All the figures, unless otherwise indicated, have a magnification of 

 20 diameters.) 



Plate i 



Fig. I. Clytia la.va: a, portion of colony showing branching, hydrothecae, and 

 long pedicels ; b, portion of fascicled stem with gonangia. 



Fig. 2. Synthccium gracile: Portion of stem showing arrangement of hy- 

 drothecae. 



Fig. 3. ScrtularcUa ornata: Portion of colony showing hydrothecae and gonan- 



gium. 



Fig. 4. Sertularia subtilis: Portion of colony showing hydrothecae. 



Fig. s. Aglaophenia curvidem: a, portion of stem showing internodes and 

 origin of hydrocladia ; b, portion of hydrocladium with hydrothecae ; 

 c, portion of hydrocladium further enlarged (X 40)- 



Fig. 6. Aglaophenia meganema: a. portion of stem with hydrocladia and hy- 

 drothecae; b, portion of hydrocladium with hydrothecae, further 



enlarged (X 40 )• 



Plate 2 



Fig. 7. Antcnnella curvithcca: a, colony showing hydrothecae; b, portion of 



colony further enlarged (X 40) • 

 Fig. 8. Halicormria longicauda: Portion of colony showing internodes of stem, 



bases of hydrocladia and goaingia. 

 Fig. 9. Hippnrella ckgans: a, portion of branch with proximal portion of 



hydrocladia ; b, face view of a portion of a hydrocladium ; c, portion 



of branch modified to protect the gonangia. 

 Fig. 10. Sireptocauhis gracilis: Portion of fascicled stem and basal portion of a 



hydrocladium with hydrothecae. 



