538 MEDUSA OF THE WORLD. 



(?) Genus CRATERLOPHUS Clark, 1863. 



Craiertophus, CLARK, 1863, Journal Boston Soc. Nat. Hist., vol. 7, p. 539. HAECKEL, i88o,Syst. der Medusen, p. 394. GROSS, 

 1900, Jena Zeit. fiir Naturwissen, Bd. 33, p. 614. MAAS, 1906, Fauna Arctica, Arktischen Medusen, Bd. 4, Lfg-3, p. 500. 



The type species is Craterlophus tet/iys of Helgoland, German Ocean. 



GENERIC CHARACTERS. 



Stauromedusae with 8 adradial lobes and with 4 perradial gastrogenital pouches in the 

 subumbrella wall of the 4 perradial stomach-pouches as in the Cleistocarpidae. Without per- 

 radial or interradial marginal anchors or marginal papillae. The peduncle is 4-chambered. 



According to Antipa, and Gross, this medusa may sometimes have 8 small tentacles, 4 per- 

 radial and 4 interradial, in the places of the anchors of other Stauromedusae. It is probable, 

 therefore, that Craterlophus is actually identical with Halimocyathus. 



Craterlophus tethys Clark. 



Lucernaria sp., METTENHEIMER, 1854, Abhandl. Scnckenberg, Naturf. Ges. Frankfurt, p. 15, taf. l, fign. 5-11. 



Craterlophus tethys, CLARK, H. J., 1863, Journal Boston Soc. Nat. Hist., vol. 7, p. 540. KLING, 1879, Morpholog. Jahrb., Bd. 5, 

 p. 141, taf. 9-11. HERTWIG, 1870, Jena. Zeitschr. fur Naturw.,Bd. 13, p. 613, taf. 9, fign. 7-12. HAECKEL, 1880, Syst. der 

 Medusen, p. 395. CLAUS, 1883, Untersuch, Uber Organisation und Entwick. Medusen, p. 35. ANTIPA, 1892, Zool. 

 Jahrb., Abth. Syst., Bd. 6, p. 392, (aboral medusa). GROSS, 1900, Jena. Zeit. fur Naturw., Bd. 33, p. 614, taf. 23, 24 

 (anatomy). KASSIANOW, 1901, Zeit. fiir wissen. Zool., Bd. 69, pp. 299, 372, taf. 22, 24, 25. 



Bell deep goblet-shaped, higher than wide, 15 to 25 mm. wide, and 25 to 30 mm. high, 

 including peduncle. Peduncle short, 4-sided, prismatic, and 4-chambered, one-fourth to one- 

 third as long as bell-height. Peduncle without longitudinal muscles. The 8 adradial arms 

 are short, wide, and 45 apart. 60 to 80 knobbed tentacles upon each arm. There are normally 

 no marginal anchors, although Antipa, 1892, and Gross, 1900, record abnormal specimens 

 with 8 small tentacles, 4 perradial and 4 interradial. 



The 8 gonads present the appearance of a 4-leaved cross, in the axes of which lie the 4 

 perradial, mesogomal pouches. The 8 arms of the gonads approach pair-wise and extend 

 under the subumbrella from base of throat-tube to bell-margin with their proximal ends 

 nearly touching. Each arm of the gonads has 10 to 16 feathery sinuosities and very numerous 

 saccules. 



Color variable, as in most of the Stauromedusae, being olive-green, yellowish, reddish- 

 brown, or dark brown. 



This form is found at Helgoland, German Ocean, where it lives upon the west coast of 

 the island upon Ulva, Chorda, or FUCHS. Gross, 1900, gives the best description of its inter- 

 nal anatomy. Kassianow, 1901 (p. 371), finds that if Craterlophus tethys be cut longitudin- 

 ally from the oral pole to the middle of the peduncle, each half regenerates a new individual. 

 If, however, the cut be not so deep the edges grow together and restore the former individual 

 although the scar remains as a constriction upon the bell and pharynx. He also reports the 

 finding of specimens of this medusa with more than 8 marginal lobes. 



Craterlophus is imperfectly separated from Halimocyathus, bearing the same relation to it 

 that Lucernaria does to Haliclystus. We may, however, retain these generic names mainly 

 as a matter of convenience. In both Craterlophus and Lucernaria the perradial and interra- 

 dial tentacles or anchors are commonly absent, but occasionally they appear as an abnormality 

 and in such cases the medusae can not be separated from Halimocyathus and Haliclystus 

 respectively. 



Craterlophus macrocystis von Lendenfeld. 



Craterlophus macrocystis, VON LENDENFELD, 1884, Proc. Linnean Soc. New South Wales, vol. 9, p. 165; 1887, Australian Museum 

 Descript. Catalogue Medusee Australian Seas, part I, p. 13. 



Umbrella deep and bell-shaped, 12 mm. high, 6 mm. wide. Stalk 8 mm. high and 3 mm. 

 wide when extended. 8 short arms 45 apart, each with a cluster of about 30 tentacles. Gonads 

 feathery, as in C. tethys. Color dark olive-green. East coast of New Zealand on Macrocystis. 

 Rare. 



