572 



MEDUSAE OF THE WORLD. 



Synopsis of the Forms of Pflagta Continued. 



*Development through a pelagic larva without strobilization or alternation of generation, Haeckel, 1867. 



Griffiths and Platt, 1895 (Nature, vol. 52, p. 564), find that the violet pigment of Pelagia 

 has the composition C 20 H I7 NO 7 . It is soluble in alcohol, ether, and acetic acid, and especially 

 soluble in CS 2 . Insoluble in water. It gives no characteristic absorption bands. It is thus 

 quite distinct from the blue coloring matter of Hydromedusae as determined by Colasanti, 1888 

 (Centralblatt fur Physiol., Bd. 2, p. 10). 



Pelagia noctiluca Pgron and Lesueur. 



Plate 60, figs, i to 3. 



Medusa noctiluca, FORSKAL, 1775, Descript anim. itin. orient., p. 109. 



Pelagia noctiluca, PERON ET LESUEUR, 1809, Annal. du Mus. Hist. Nat., tome 14, p. 350; P. pur/tura, Aurrllia plio.<[>horica, 

 loc.cit., pp. 350, 358. KROHN, 1855, Miiller's Archiv. Anat. Physiol., p. 491, taf. 20 (development). HAFCKF.L, 1880, 

 Syst. der Medusen. p. 505 (list of authors and names). KOWAI-EVSKY, 1873, Mem. Imp. Sue. Lovers of Nat. Hist.. 

 Moscow, vol. 10, part. 2, p. 7, plate 3 (development). HAMANN, 1883, Zeit. fur wissen.Zool., Bd. 38, p. 422, taf. 32 (develop- 

 ment and structure of gonads). METSCHNIKOFF, 1886, Embryol. Studien an Medusen, Wien., p. 24 (egg); 67 (segmenta- 

 tion); loo (larva); taf. 10, fign. 23-28. MONACO, Prince of, 1887, Comp. Rend. Paris, tome 104, p. 452 (swarming habits 

 of the medusa). VANHOFFEN, 1888, Bibliotheca Zoologica, Heft. 3, p. 8, taf. I, fign. 5, 6; taf. 6, fign. 1-5; 1908, Deutsch. 

 Siidpolar Expedition, 1901-1903, Bd. 10, Zool. 2, p. 38. GOFTTE, 1893, ^ e i r - rur wissen. Zool., Bd. 55, p. 659, 1 1 fign., 

 taf. 30-31; 1893, Sitzungsber. Akad. Wissen. Berlin, p. 853 (development). SCHAXEL, 1910, Zool. Anzeiger, Bd. 35, p. 

 407 (histology of obgenesis). 



The following is a description of a typical, adult specimen from the Bay of Naples: 

 Disk somewhat higher than a hemisphere when contracted, but flatter than a hemisphere 



