130 



THE ANATOMY OF INVERTEBRATED ANIMALS. 



condition the gonophores of Atkoryhia may be cited (Fig*. 

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

 Velella. 



In Athoryhia, groups of gonophores, together with pyri- 

 form sacs, which resemble incompletely develoj^ed hydranths 

 (hydrocysts — Fig. 27, -4, a), are borne upon a common stem, 

 and constitute a gonohlastidium, (Fig. 27, A), The groups 

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

 upon separate branches of the gonohlastidium (androphores 



Fig. Vl.—Athoryhia rosacea.— A, gonoblastidium bearincr three hydrocysts, a ; gyno- 

 phore, b ; and two androphores, c. B, female gonophores on their common i<tem 

 or gynophore, showinir the inchidod ovum, a, and the radical canals, b. O, X>, 

 female gonophores enlarged ; a, germinal vehicle ; b, vifellua; c, radial canals of 

 the imperfect nectocalyx ; d, canals ol the manubrial cavity. E, male gouophore, 



and gyjiojihores). Each female gonophore contains only a 

 single ovum, which projects into the cavity of the imperfectly 



