130 



THE ANATOMY OF INYERTEBRATED ANIMALS. 



condition the gonophores of Athoryhia may be cited (Fig. 

 27) ; of the latter, the gonophores of Physalia^ Porpita, and 

 Velella. 



In Athoryhia, groups of gonophores, together with pyri- 

 form sacs, which resemble incompletely developed hjdranths 

 (hych'ocysts — Fig. 27, v4, «), are borne upon a common stem, 

 and constitute a gonohlastidiura (Fig. 27, A^. The groups 

 of male and female gonophores (Fig. 27, A^ h, c) are borne 

 upon separate branches of the gonoblastidium (cmdrojihores 



Fig. 27. — Athoryhia rosacea.— A^ gonoblastidinm bearing: three hydrocysts, a; gyno- 

 phore, h ; and two aiidrophore>^, c. B. female gonophores c.i their common stem 

 or gynophore, showinir the included ovum, «, and the radical canals, b. C, D, 

 female gonophores enlarged ; a, terminal vesicle ; b. vitellus; r, radial canals of 

 the imperfect nectocalyx ; d, canals of the manubrial cavity. E, male gonophore. 



and gynopJiores). Each female gonophore contains only a 

 single ovum, which projects into the cavity of the imperfectly 



