PLATE 20. 



Stephanomia bijuga. 



Fig. 1. A siphon with tentacle and three bracts of successive ages (Br^, Br^, Br^). X 20. 



Fig. 2. A segment of the stem from between two successive siphons, with palpon (p), and male 

 and female gonodendra (Go. cf, Go. 9). X 20. 



Fig. 3. Tentilla from the primary tentacle of the young colony represented in PI. 19, fig. 11. 

 X35. 



Nectalia loligo. 



Fig. 4. General view of colony. X about 2.5. 



Fig. 5. Nectophore. 



Fig. 6. Archisoma natans. General view of free Eudoxid (p. 266). X 3. 



Anthophysa rosea. 



Fig. 7. General view of colony 13 mm. in diameter. The bracts have been removed, but their 

 positions are indicated by the muscular lamellae (L. Mu). 



Fig. 8. A young tentillum of the tricornuate type. X 50. 



Fig. 9. Half-grown tentillum of the dendritic type. Cf. PL 23, fig. 4, which shows the adult 

 tentillum of this type. X 50. 



Fig. 10. Adult tricornuate tentillum. The involucre, bearing a marginal spur (x), entirely encloses 

 the two complete turns of the coiled cnidoband. X 40. 



Fig. 11. A palpon with its filament (F). 



Fig. 12. A portion of the ventral surface of the denuded corm, showing the extremities of one 

 group of muscular lamellae (L. Mu) ; and the relative positions of male and female gonophores (Go. 

 cf , Go. 9 ) and palpons (P). Most of the organs are broken off. X 20. 



Fig. 13. A reconstructed radial section of the corm, showing the septa, and on the exterior the 

 muscular lamellae (L. Mu), the siphons (S), and a pair of gonodendra, male and female (Go. <f, Go. 

 9). Pn. C pneumatoeodon, Pn. S pneumatosaccus. X 7. 



