NARCOMEDUS^E PEGANTHA. 



439 



Genus PEGANTHA Haeckel, 1879, sens, emend. 



Polxxenia + Pewia+Pepantha+Solmoneta, Haeckfl, 1879, Syst. der Medusen, pp. 331, 353- 



Mk Eh£», .88., Report C1A F Expedition, Zool, vol. 4, P- 3 6--Maa», ,893, Ergeb. dcr Plankton Exped, ,.nn, 

 g Bd. ^K.c/p. 47.-B.GELOW, ,904, Bull. Museum. Comp. Zool. at Harvard College, vol. 39, p. 260; .909, Mem. 



IbiJ.,'x>. 83. „ . 



( i)Pega:ia, Peron et I.esuelr, 1809, Annal Mus. Hist. Nat. Paris, tome 14, p. 340. 

 (>)Po)yxenia, Eschscholtz, 1829, Syst. der Acal., p. 118. 



GENERIC CHARACTERS. 



Solmarid* with a variable number of tentacles alternating with an equal number of 

 marginal lappets. The gonads are found in a zone of evaginated sacs which arise from the 



291. 



293- 



294- 



Fig. 291 .—Pegantha goddefjroyi, after Haeckel. 



Fig 202 — Pegantha aureola, after Haeckel, Syst. der Medusen, taf. 19, fig. II. 



Fig zl\.-Peganlha triloba, oral view, after Mayer, in Bull V. S. Bureau of Fisheries. 



Fig. ^.-Pegantha < ri,oba < side vieW > aftCr May "' ' n BU "- U ' S ' BUrea " Flshe " eS - 



subumbrella floor of the stomach, one or more in each lappet-radius. There may or may not 

 be ectodermal, sensory tracts over the exumbrella above the marginal sense-clubs. A per.ph- 

 eral ring-canal system appears always to be present. 



According to Haeckel, Pegantha is distinguished by the condition that the gonads are said 

 to be confined to intertentacular outpocketings from the subumbrella floor of the stomach 

 and are not developed upon the general subumbrella floor of the central stomach itself. 



There is unfortunately, however, no sharp line of demarcation between Pegantha, wherein 

 the o-onads are confined to intertentacular saccules, and Haeckel's Polyxenta, wherein the 

 gonad consists of a ring on the subumbrella floor of the stomach and also extends downward 

 in intertentacular saccules from the floor of the stomach in the radii of the lappets. 



Haeckel distinguishes Pegantha with ectodermal sensory tracts above the sense-clubs 

 and Sohnoneta without these'appendages. This difference appears to me to be too slight to be 

 of more than specific value. 



35 



