Hydrozoa and Poly zoa from the China Sea. 13 



raents. Length of hydrothecse *4 to '5 millim., breadth - 1 

 millim. 



Sarcotheca? numerous, cylindrical, varying in length from 

 *1 to '4 millim., on the tubes composing the main stem and 

 larger branches ; a pair at the base of each hydrotheca. 



Gonosome unknown. 



Hah. Tizard Reef, 35 fath. 



The type of the genus Zygophylasc is Z. profunda , Quelch*, 

 from Cape-Verde Islands, 500 fath. 



The nearest ally to Zygophylax is the genus Perisiphonia~\ 

 of Allman ; in the latter the colony is polysiphonic through- 

 out. The genus Cryptolaria includes forms in which the 

 colony is entirely polysiphonic (as in Cryptolaria prima, 

 Busk) and others in which it becomes monosiphonic towards 

 the periphery. It would appear, then, that Perisiphonia is 

 synonymous with Zygophylax. 



The knobbed ring at the base of the hydrotheca in Z. tizard- 

 ensis gives attachment to muscular fasciculi which unite to 

 form a sheath (retractor muscle) surrounding the offset of the 

 ccenosarc as it enters the hydrotheca ; the protractor muscle 

 is attached to the chitinous half-ring on the upper dorsal part 

 of the hydrotheca. 



Genus Stephanoscyphus, Allman. 



Stephanoscyphus, Allman, Trans. Linn. Soc, 2nd ser. Zoology, vol. i. 

 1875, p. 61. 



Stephanoscyphus Allmani, n. sp. (PI. III. fig. 1.) 



Perisarc consisting of a monosiphonic, stout, irregularly- 

 branched stem, straggling, flexible, partly decumbent, partly 

 free ; about "9 millim. in diameter, marked with circular rugaj 

 and longitudinal striai. 



Hydrotheca? sessile, arranged in half- verticils on decumbent 

 part, and in verticils of from three to five in free portions 

 of stem ; expanding gradually from base upwards, from 3-6 

 millim. in height, with strongly marked circular ruga?, con- 

 nected by parallel longitudinal striae. Inside the hydrothecaj 

 a vertical chitinous lamella expanding into a funnel or basin 

 with thick, free, fimbriated edge closing in about three fourths 

 of the lumen of the tube ; sometimes a second chitinous process 

 higher up in the tube. 



Bab. Tizard Reef, 27 fath. 



In consideration of the interest taken by Prof. Allman in 



* Ann. & Mag. Nat. Hist, (5) xvi. 1885, p. 4, pi. i. fig. 4. 

 t ' Challenger ' Report on Hydroida, pt. ii. p. 48. 



