CNIDARIA 



121 



dorsal tufts [Dorsalcrisjyen] of the lower part of the arm arise. The 

 fundaments of the shoulder tufts [Schulterkrausen] , or scapulettes, arise 

 in pairs as papillary elevations in the eight radii, and only subsequently 

 assume an adradial position (Claus). The lateral margins of the arms, 

 which are bent under, now grow together, so that there arise from the 

 brachial furrows closed canals, which open to the outside world by 

 means of the so-called funnels, rhizostomes or oscula suctoria (originally 

 lateral folds of Ihe margins of the arms). As the last trace of the 

 mouth, closed by concrescence, we find the central cruciform oral raphe. 



Pig. 62. — Diagram of an interrailial longitudinal section through a Scyphome- 

 dusa (based on a figure by Claus). R, radial vessel; Rk, marginal bodies [rho- 

 paha] ; ol, ocellar lobes; Gs, genital sinus; G, genital band; Gf, gastral fila- 

 ments; Gmi, gastro-genital membrane ; S, sub-genital sinus. 



An account of the metamorphosis of one of the Versuridse (Stylorhiza 

 punctata) has been given by v. Lendenfeld (No. 110). 



We have still to mention certain organs which are de- 

 veloped at the places originally marked hy the four 

 degenerating columellfe, i.e. in the interradii. These are, 

 first of all, the gastral filaments and the genital hand. In the 

 youngest Ephyree only one of the gastral filaments, which 

 originally budded forth as tentacle-like growths at the 

 base of the columelljE (Fig. 57 gf), is found in each inter- 

 radius. However, their number is soon increased (Fig. 58 

 gf), and finally numerous filaments occur, usually arranged 

 in a curved line corresponding to the inner side of the 



