520 



MEDUS-E OF THE WORLD. 



Capria, Lipha, Lucernaria and Haliclystus represent the more simply organized Eleuthero- 

 carpidx A clear understanding of these relations can best be obtained from a study ot the 

 fic'ures bv Gross, 1900 (Jena. Zeitsch. fiir Natunvissen., Bd. ^t,, p. 613, tat. 23, 2+). Bt;ing 

 imemal charaaers, I have not made use of them in the classification of the Stauromedusae. 



As one would expect in sessile animals the Stauromedusae show evidences of degeneration, 

 loss of marginal lobes or of tentacles; and in none of them do we find the lithocyst-beaiing 



Fig. 332^. — Median longitudinal pcrradial uctiuns and cross-sections of Stauromedusx. Somewhat diagrammatic, after Gross. 



A. The internal anatomy of the Clcistocarpidx illustrated by Craterlophus tethys. 



B. Hie internal anatomy of Elcutherocarpidx illustrated by Haliclystus. The cross-partition ^ or claustrum (C), is 



found in the Cleistocarpida; but is absent in the Elcuthcrocarpidx, 

 In both figures: C, transverse partition spanning between gonads; ex^ outer chamber; fcy funnel-pits containing 

 longitudinal nucleus; gt gonads; gr, gastric cirri; /m, longitudinal muscles; i, intcrradial septa. 



sense-organs seen in all other orders of Scyphomedusae. Eyes and "otocysts" are absent in 

 the Stauromedusze, and pulsation is not exhibited by the sessile forms. 



There is reason to believe that the Stauromedusae are the most degenerate of all Scypho- 

 medusx and are to be regarded as sexually mature Scyphostomae (see Kassianovv, 1901; 

 Goctic, 1887). Their degeneracy is amply accounted for by their sessile mode of life; Ilornell, 

 1883 rXatural Science, London, vol. 3, p. 204), and Hurst (Ibid., p. 209) believe that they are 



