Boone, Coelenterata, Cruises of "Ara" and "Alva" 47 



width diameter of the bell. Eight marginal sense organs are 

 present set in deep niches, interradial and perradial. The sense 

 club has no ocellus, having only a terminal, crystalline, orange- 

 colored concretion mass. There is no sensory pit in the exum- 

 brella above the sense club. There are sixteen marginal lappets, 

 each being subrectangular with rounded angles and shallow 

 median notches. The four-sided throat-tube is one-half as long as 

 the bell diameter and the four lanceolate palps, each with their 

 multi-folded margins are about one and one-third times the bell 

 diameter. The outer edges of the palps have verrucae similar to 

 those of the exumbrella. 



Colour : The bell of the medusa is rose tinged with light laven- 

 der, this purplish tone deepening in the gonads and tentacles. The 

 verrucae of the exumbrella and palps are brownish-orange-red. 



References: Medusa noctiluca, Forskal, P., Descript. Anim. 

 Itin. Orient., 1775, p. 109. 



Pelagia noctiluca, Peron, F., et Lesueur, C. A., Ann. Mus. Hist. 

 Nat. Paris, 1809, t. XIV, p. 350.— Krohn, A., in Muller's 

 Archiv. Anat. Physiol., 1855, p. 491, taf. 20, (discusses de- 

 velopment). — Haeckel, E., Densksch. Med.-Naturwiss. 

 Gesell. Jena, Syst. der Medusen, 1880, Bd. I, p. 505 (with 

 extensive early synonymy). — Kovalevski, A. 0., Mem. Imp. 

 Soc. Lovers of Nat. Hist. Moscow, 1873, t. X, pt. II, p. 7, pi. 3, 

 (discusses development). — Hamann, 0., Zeit. f. Wissensch. 

 Zool., 1883, Bd. XXXVIII, p. 422, taf. 32, (development and 

 structure of gonads). — Mechnikov, I. I., Embryol. Studien 

 Medusen, Wien, 1886, p. 24 (egg), p. 67 (segmentation), p. 

 100, (larva), taf. 10, figs. 23-28.— Monaco, Prince Albert 

 of, presented by Edwards, A. M., Compt. Rend. Sci. Paris, 

 1887, to. CIV, p. 452, (swarming habits of this medusa). — 

 Vanhoffen, E., Bibliotheca Zoologica, 1888, heft No. Ill, p. 8, 

 taf. 1, figs. 5, 6, taf. 6, figs. 1-5; Deutsch. Sudpolar Exped. 

 1901-03, Bd. X, Zool. II, p. 38.— Goette, A., Zeit. f . Wissensch. 

 Zool., 1893, Bd. LV, fig. 11, taf. 30-31; Sitzber. Akad. Wis- 

 sensch. Berlin, 1893, p. 853 (development). — Shaxel, J., 

 Zool. Anz., 1910, Bd. XXXV, p. 407 (histology of oogenesis). 

 — Mayer, A. G., Medusae of World, Carnegie Inst. Wash. 

 Publ. 109, vol. Ill, 1910, p. 572, pi. 60, figs. 1-3, colour. 



