642 



MEDUSAE OF THK WORLD. 



FIG. 402. Cassiopea xamachana, after R. P. Bigelow, in Mem. Boston Soc. Natural History. 



bj bud growing from side of scyphostoma; cd, circum-oral disk or peristome; t7, interrhopalial lobe; tt, 

 interrhopalial tentacle; m, mouth; p, proboscis; r/;/, rhopalial tentacle; /, tentacle. 



25, strobila, in which the degeneration of the rhopalial tentacles is nearly complete and the interrhopalial 

 tentacles have begun to degenerate. 26, a complete strobila. The basal polyp bears a bud which 

 broke of! and swam away while the drawing was being made. The ephyrula was detached during 

 the following night. The rhopalia are visible through the umbrella. At y is a pair of twin 

 rhopalia (compare Vj fig- 30). 27, basal polyp of same specimen, a few hours after separation of 

 the ephyrula. 28, optical section of same. 29, an ephyrula recently set free; oral aspect, gastric 

 filaments visible through mouth; X 31. 30, specimen of about same age, showing variations of 

 margin at u, w, y and 2; X 31. 



