42 THAUMANTIAS PILOSELLA. 



A. Marginal tentacles of two kinds (Cosmetira). 



1 . Thaumantias pilosella. 



B. Marginal tentacles of one order only (Thaumantias). 



* Marginal tentacles four. 



2. T. quadrata. 



3. T. aeronauiica. 



** Marginal tentacles eight. 



4. T. octona. 



*** Marginal tentacles sixteen and upwards. 



•j- Umbrella very convex or globose. 



5. T. maculata. 



6. T. melanops. 



7. T. glohosa. 



8. T. convexa. 



9. T. gibbosa. 



ft Umbrella depressed. 



10. T. lineata. 



11. T. pileata. 



12. T. Sarnica. 



13. T. Thompsoni. 



14. T. hemisphcBrica. 



15. T. inconspicua. 



16. T. punctata. 



17. T. lucifera. 



A. Marginal tentacles of two kinds. 



[Cosmetira.] 



1. Thaumantias pilosella, Forbes. 

 Plate VIII, Fig. 1. 



By far the most beautiful, and among the largest, of the British kinds of Thaumantias is 

 that I have first to describe. The umbrella, which sometimes measures nearly two inches in 

 diameter, but more usually one, or one and a quarter, is hemispheric, and shaped like a watch- 

 glass, but much more convex. It is transparent and smooth, except on the sides towards the 

 margin, where it is as if woolly, being invested with minute epidermic hairs composed of fibrous 

 cells. These, though sufficiently conspicuous, may escape the observer who is not aware of their 

 presence, in consequence of their transparency. The margin is fringed by very numerous 



