Variation in Aurelia awrita. 



127 



A. aurita shows eight marginal lobes, eight unbranched canals, eight 

 tentaculocysts or marginal sense-organs, four sets of gastric filaments, and 

 four mouth lappets, while a normal mature adult shows eight branched canals 

 (four perradial and four interradial), eight unbranched canals (the adradials), 



/A<-. 



T.C. 



'^Jx c:' 



Fig. 1. 



Normal Aurelia aurita. 



p.e. Perradial canal system. 



i.e. Interradial canal system. 



«.<.'. Adradial canal system. 



tt. Tentaculocyst. 



te. Tentacle. 



r.c. Ring canal. 



g.s. Genital sac with gonad. 



in. Manubrium (the four oral lobes not shown in diagram). 



eight tentaculocysts (at the margin of the bell and at the end of the branched 

 canals), four genital sacs (with gonads), a four-lipped manubrium (with the 

 angles situated perradially), a ring canal, and a fringe of tentacles round 

 the outer edge of the umbrella (Fig. 1). In normal examples of even 

 very immature adults, these tentaculocysts, genital sacs, oral lips and 



