THE HYDROMEDUSAE 





Fic. 13. 



Fli;. 1:^ 



Me 



Fio. 14. f 10. i:., 



11 -Ocellus of /-una KocUikeri. or, i)igiiient«i ectodonnal cells ; I, lens 



1> -Otocyst of FhiaMUim. U\ superticial layer of ectodenn ; d2 deep layer of ecto- 



dona- ;, auditory cells of ectodenn : ;./,, auditory hairs; «;,, nene body ; nrl. upper nerx-.. 



ring -'r endodeni. c.-lls of the circular canal. The otolith cavity is seen above h. (tigs. 



"' lMn:;cys;'oft:7.?^!;:^ ";^UU. = renmlning letle,. as Fig. 12. (After Hert^g.) 



4-Siini)le tenUiculocvst of one of the Trachon.edusae {Ulw,mhna,ia li-Muvi). 1 he i)rocess 

 carrying the tolith or concretion hk, fonned by endodonn cells, is enclosed by an upgrowth 

 fZi« the ''vesicle." which is not yet quite closed in. (From Lankesler, after Ilertw.g.) 



5 -optical section of a conJylus or sense club; the surround.ng strnctun-s an- onl.v 

 rouitlv indicated. VC, circular canal; FA', exun.bral surface; J»/<- niesogloea ; A/f, tl..' 

 outer, Av" the inner parts of the ne^^'e ring; SV, submubral surface; 7. tenUcle ; I. 

 velum. (After Urooks.) 



