I2 MEDUSAE. I. 



Lat. 4804* N., Long. 3225' W. July i5th 1910. "Michael Sars" stat. 84. -- a. Ringtrawl, 2500 m 

 wire, i specimen, diam. 26 nun. - - b. Young-fish trawl, 3000 m wire, i specimen, diam. about 27 mm, 

 about 24 tentacles. 



Lat. 545i' N., Long. 28i5' W. July i;th i8th 1913. 1000 m wire. "Armauer Hansen" stat. 9. - 

 3 specimens: i. Diam. about 17 mm, three-rayed. 2. Diam. 19 mm, height 15 mm, 20 tentacles. 3. A large, 

 defect specimen. 



LaL 5405' N., Long. 26o8' W. July isth 1913. 1000 m wire. "Armauer Hansen" stat. 7. - 2 

 specimens, diam. 18- 22 mm. 



Lat 6i34' N., Long. I9O5' W., Irminger Sea. July zoth 1904. Depth 2160 m. Young-fish trawl, 

 probably 1800 m wire. "Thor" stat 180 (04). - - i specimen, diam. 14 mm. 



Lat. 6ii5' N., Long. 935' W., north-west of the Faroe Bank. May 22nd 1904. Depth 872970 m. 

 Young-fish trawl, 10001700 m wire. "Thor" stat. 99 (04). - - i specimen, diam. 15 mm, about 16 tentacles. 



The specimens from the "Michael Sars" and the "Armauer Hansen" are in Bergens Museum, 

 the specimens from the "Thor" and the "Tjalfe" are in the Zoological Museum of Copenhagen. 



Among the 5 specimens from the "Armauer Hansen" two are abnormally developed. One 

 specimen from stat. 9 has only three radial canals; a specimen from stat. 7 shows the following features: 

 It is a female individual, 22 mm in diameter. One of the four radial canals bifurcates at the point of issue 

 from the stomach, forming two complete gonadial systems; at the distal ends of these the two branches 

 of the canal unite once more, so that the distal part of the canal, free of gonads, is simple. Two others 

 of the canals, otherwise normally shaped, converge very much in their distal parts and reach the 

 circular vessel so near each other, that only one tentacle finds room between them. 



The distribution of Chromatoncma rtibrum (see Chart I) is true oceanic and extends over the 

 deep basins of the North-Atlantic on both sides of the submarine ridge which divides the Atlantic 

 into a western and an eastern basin. The distribution of the species in the western basin extends 

 northwards to the southern slope of the submarine ridge between Greenland and Baffin Land. In the 

 eastern basin the north-limit of the distribution is the Wyville Thomson ridge. With two exceptions, 

 viz. M011er 1843 ( see below) and "Thor" Stat 99 (depth 872 970 m), all of the localities are from 

 outside the 1000 m line. The specimens mentioned by Fewkes were taken on the slope outside the 

 coast of New England south of Cape Cod. The "Michael Sars" found the species on the southern slope 

 of the Newfoundland Bank (depth noo m) and east of the same bank (depths more than 2000 m). The 

 specimens brought home by the "Armauer Hansen" were found near the 3000 m line, and by the 

 "Thor" the species was found outside the 2000 m line south of Iceland (stat. 180), and near the 1000 m 

 line north-west of the Faroe Bank (stat 99). The "Tjalfe" found it between 1046 and 1300 m in the 

 Davis Strait 



The species has mostly been found far below the surface of the ocean, between 600 and 2000 m, 

 i. e. in the true oceanic water. Thus in the Gulf-Stream area the species does not, as a rule, rise to 

 the water-masses of that current, but keeps itself in the deeper and colder water layers. The "Michael 

 Sars" stat. 70 on the southern edge of the Newfoundland Bank is north of the northern limit of the 

 Gulf-Stream ; here a specimen was caught about 400 m below the surface. 



