MEM. M. C. Z., IX. No. 3. — ACALEPHS, POLYPS. 31 



42. Ephyi'a with umbrella {ubv) thrown back, leaving the manubrium {man) projecting outward, ga. c. Gastric 



chamber (in this early stage only a part of the stomach), naj. Otocyst. tb. Tube to the otoeyst from the 

 gastric chamber, tb.' Tube from the gastric chamber to the region from which the tentacles later arise. 



43. Ephyra of about the same age as the last from the aboval side. ga. c. Gastric chamber, or. Mouth seen 



through the body walls. <6.i Tentacular tube, tb.'^ Tube to the otocyst. 



44. An older Ephyra seen fronj the oral side. ga. c. Gastric chamber, o cy. Otocyst. m-. Mouth, lb.' Tentac- 



ular tube, tb.- Ocular tube. ubr. Umbrella. 



45. A sense octant (from oral side) of an Epliyra of about this age. ocy. Otocyst. ocy. n. .Stalk upon which 



the otocyst is carried, tb.' Chymiferous tube from gastric chamber to the region of tlie liell margin from 

 which the tentacles arise, tb.'^ Tube to tbe peduncle of the otocyst. tb.^ Blindly ending tube, th.^ En- 

 largement of ocular tube. 



46. Quadrant of an Ephyrn (oral view), older than the last in which the clusters of tentacles are formed, can. 



c»-c. Circular canal, ga. Stomach, lab. hips. oa. Ovary, ocj/. Otocyst. or. Mouth, ta-to.^ Tentacles. 

 ib-ib .' Chymiferous tubes, vel. Velum, f, f.' Intervals of muscular lower floor separating tubes. The 

 circular muscles are seen at f. ' 

 46.1 Ovarian opening, oa. Ovary, y. Portion of bell-wall near ovary, a. Eim of opening. </>. Phacellen (sex- 

 ual fdaments). 0.' Phacellen, seen through opening. 



47. Profile view of a young medusa, older than the Ephyra strictly so called, with bell e.\panded. ocy. Otocyst. 



or. Mouth, or. ta. Oral tentacles, tibr. Upper side of the umbrella. 



48. The same with bell-walls contracted, or. ta. Oral tentacles. 



49. Oral view of a young medusa older than the Ephyra, but without tentacles. 



