Plate 35. 



Fig. 1. Phialidium mccradyi. Oral view of the medusa. Tortugas, Florida, 

 July, 1898. 



Fig. 2. Phialidium mccradyi. One of the hydroid blastostyles that are 

 produced upon the gonads of the medusa. 



Fig. 3. Phialidium mccradyi. Side view of one of the gonads. 



Fig. 4. Pseudoclytia pentata. Side view of the medusa. For oral view of 

 manubrium see figure 7, plate 36. Tortugas, Florida, July, 1898. 

 See page 278. 



Fig. 5. Pseudoclytia pentata. A tentacle-bulb of the medusa shown in 

 figure 4. 



Fig. 6. Pseudoclytia pentata, red variety. Tortugas, Florida, July 22, 1898. 



Fig. 7. Gastroblasta ovalis, oral view of a medusa with 4 manubna. Tor- 

 tugas, Florida, June 30, 1899. See page 281. 



Fig. 8. Gastroblasta ovalis. Side view of a medusa with 4 manubna and 2 

 gonads. Tortugas, Florida, July 1, 1899. 



Figs. 9 and 10. Phialidium singulans. Figure 3' shows a part of the bell- 

 margin of the medusa shown in figure 3. Agassiz Laboratory, 

 Newport, Rhode Island, August 22, 1896. See page 273. 



Drawn from life, by the author. 



