Royal Physical Society. 255 



web or funnel was studded with thread-cells of very large size, 

 ranged along each side of the tentacles. (Plate XIV., fig. 1.) 

 Similar large cells were also found scattered on the body of 

 the polyp. 



In September last, buds were put forth from the foot of 

 many of the polyp stems, which became slowly developed 

 into cylindrical capsules, supported on long pedicles, and of 

 large size compared with the minute polyps to which they 

 were attached. As I was obliged to leave home at that time, 

 I examined the capsules, and found in each a single large 

 Acaleph or Medusoid, imperfectly developed within a fleshy 

 sac, which was thickly covered with large thread-cells. 

 During the present month similar capsules again appeared ; 

 and Alcmena never wearied more of her prolonged gestation 

 of Hercules than I did, as day after day these capsules slowly 

 increased in size and revealed the young giant within. At 

 length fierce throes commenced ; but Latona sat cross-legged 

 at the threshold for a night and a day before the sac burst, 

 and a pale-emerald green medusoid was brought forth. The 

 umbrella of the Acaleph is colourless, and sub-hemispherical, 

 becoming mitrate during contraction. It is covered with 

 the large thread-cells, which are congregated in greater num- 

 bers about the middle and upper parts, and give the animal a 

 shiningly dotted, or gemmed appearance. The sub-umbrella 

 is tinted witn pale emerald-green by reflected light, and 

 is colourless or faintly orange by transmitted light ; effects 

 probably due to interference of light produced by the fibrous 

 structure of its highly-developed contractile layer. The sto- 

 mach or alimentary polyp is quadrangular. The tentacles or 

 prehensile polyps are four in number — two long and two rudi- 

 mentary ; they are ringed as to their bulbs with deep blue, 

 and are without eye- specks. The auditory capsules are eight 

 in number, situated one on each side of the four tentacles. 

 The tentacles and alimentary polyps are furnished with small 

 thread-cells. The Acaleph has no ovaries or sperm-sacs. 



The general appearance of this Acaleph resembles that of 

 the Acaleph of Campanularia Johnstoni (Alder), of which Mr 

 Gosse has given a figure in his " Devonshire Coast." 



Great numbers of the Acalephs of Z. acuminata were given 



