CASSIOPEA XAMAOHANA. 235 



PLATE 33. 



Fig. 26. St,ri>l)ila, in which the degeneration of the rlmiialial tentacles i.s nearly completed, and the iiiterrhopalial 

 lentacle.s have begun to degenerate. 



Fig. 26. A complete strobila. The ba.sal polyp bears a bud which broke off and swam away while the drawing was 

 being made. The e|ihyriUa was detached during the following night. The rliopalia are visible through the umbrella. 

 At y, is a pair of twin rhopalia ; couipare y. Fig. 311. 



Fig. 27. Tiie basal polyii of the same specimen, a few iKuirs after the separation of the ephyrula. 



Fig. 28. Optical section of the same. 



Fig. 29. An ephyrula recently set free. Dral aspect. The gastric filaments are visible tlirougli the moutli. x 31. 



Fig. 30. A specimen of about the same age, showing variations of the maigin at it, lo, x, y and z. X 31. 



PLATE 34. 



Fig. 31. Mcjutli parts of a young metlusa in the Aurosa stage. The gastric filaments may be seen through the central 

 mouth opening. X 33. 



Fig. 32. Oral disc of an older specimen. The oesophageal tubes appear as light areas, one at the junction of each pair 

 of labial grooves. 



Fig. 33. One of the oral arms from the same specimen as Fig. 32. 



Fig. 34. Floor of the stomach and the oral arms of an adult viewed from the aboral side. The roof of one subgenital 

 cavity is Eemoved, and a thread is represented as passing through the external orifice into this cavity, at j. The ultimate 

 branches are represented on only one of the oral arms. 



Fig. 35. Portion of the aboral surface of an adult. About half natural size. 



PLATE 35. 



Fig. 36. Section of a young bud. X Zeiss DD + oc. 2.' 



Fig. 37. Diagram to show the branching of the septal muscles, sni^, sin,„ sm^ ajid siti^, and the connections of the 

 septal muscles of the bud, S7n\, sm',, and sm'.^. Reconstructed from the series of sections of which Fig. 36 is one. 



Fig. 38. Section through the distal apex of an older bud, showing the attachment of a septal umscle to the ectodermal 

 epithelium. X Zei.ss II + oe. 2. 



Fig. 39. Longitudinal section of a planula-like larva. D was the distal, and P the proximal, end of the bud while 

 attached. X Zeiss DD + oc. 2, dt. lOd. 



Fig. 40. Longitudinal section through the posterior end of a swimming larva, in which changes preparatory to the 

 formation of the mouth are taking place. X B &, L J + Zeiss oc. 2. 



Fig. 41. Similar section of a .slightly older larva, showing the mouth as a small opening not exceeding in width the 

 thickness of the .section. X B & L J + Zeiss oc. 2, dt. 160. 



Fig. 42. Adradial .section of a scyphistoma a little older than Fig. 9 (6th day). X Zeiss DD + oc. 2. 



Fig. 43. Obliquely transverse section of a specimen of the same age, showing the greatest width of one septum. X B 

 & L J + Zeiss oc. 2, dt. 160. 



Fig. 44. A tangential section of an older larva, showing the connection of a septal muscle with the circum-oral disc. 

 X Zeiss H + 00. 2. 



PLATE 36. 



Figs. 46 to 47 are consecutive transverse .sections of one individual. Fig. 45 shows the continuity between the endoderm 

 of adjacent gastric pouches at the base of an intenadial tentacle. Fig. 47 is lower, and here the gelatinous .septum com- 

 pletely separates the two pouches. X Zeiss H -|- oc. 2. 



^ Unless otherwise iifited, the microscoite was used with the draw tube ni»t dra\vii out. Lenj^tli of tube oit.) = 137 mm. 



