40 



MEDUS.E OF THE WORLD. 



near the mouth are only about half as long as those of the lower circlet. In addition to these 

 there are about 25 long, tapering, hollow tentacles in a zone surrounding the base of the 

 polypite. During the breeding season, which occurs from January until May, great numbers 

 of medusae are developed upon the sides of the polypite immediately above the circlet of 

 basal tentacles. The budding medusae arise singly from the sides of the polypite and are not 

 produced in clusters upon peduncles as in Hybocodon christina, H. chilensis, and H. pulcher. 

 Longitudinal bands of orange pigment extend up the stem of the hydroid. The entoderm 



FIG. 10. Hydroid, young, and budding medusse of Hybocodon prolifcr, after L. Agassiz, in Con. Nat. Hist. U. S., vol. 4. 



(A.) Mature hydranth. (B.) Oral eltremity of hydranth. (C.) Dissection showing intertentacular zone of medusa-buds. 



Remaining figures are of medusa-buds and young medusae. 



of the polypite is orange. L. Agassiz has shown that the entoderm of the stem is thrown 

 into longitudinal ridges which form partial septa projecting into the cavity of the stem. The 

 cavity, however, is continuous, and the septa do not fuse as in some other Hyboconidae. 



This species is found upon the New England coast. According to Browne, 1896, it is 

 found upon the British, and also on the Irish coast, at Valencia, and off Iceland (Steen- 



