LEPTOMEDUS.E — COSMKTIRA, CLYTIA . 



261 



GENERIC CHARACTERS. 



Eucopidae with 8 adradial, open lithocyst-sacs each containing numerous concretions. 

 With 2 sorts of tentacles, hollow marginal tentacles with swollen basal bulbs provided with 

 ocelli, and small solid cirrus-like tentacles that arise from the exumbrella as well as from the 

 bell-margin. 4 radial-canals. No peduncle. No excretory papillae. 



Cosmetira pilosella Hartlaub. 



Thaumantias pilosella, Forbes, 1848, British Naked-eyed Medusae, p. 42, plate 8, fig. I. 



Cosmetira pilosella, Hartlaub, 1909, Zoolog. Anzeiger, Bd. 34, p. 82, fign. 1-4. 



Eucheilota pilosella, Browne, 1896, Proc. Zool. Soc. London, pp. 481, 484, plate 16, figs. 7, 7a, 



Hartlaub rightly believes this medusa to be identical with Thaumantias pilosella Forbes, 

 1848; and he gives a very complete description of it based upon the study ot 8 specimens from 

 the Fjords of Norway. 



Bell 20 mm. wide, moderately rounded, without a true peduncle. About 64 short, hollow 

 tentacles with swollen basal bulbs arise from the bell-margin. These tentacles are regularly 

 bestrewn with nettle-cells and there is a dark purple ocellus on the exumbrella above the base 

 of each of the older tentacles. There are about 6 short, straight, solid, cirrus-like tentacles 

 upon the bell-margin between each 2 of the large tentacles. These lack basal bulbs and have 



no ocelli and their nettle-cells are 



arranged in rings around them. 

 These solid tentacles are hardly 

 longer than the basal bulbs of the 

 hollow tentacles. It is most remark- 

 able, however, . that these cirrus- 

 shaped tentacles arise not only from 

 the bell-margin but they project also 

 from the peripheral third of the sur- 

 face of the exumbrella. Most of 

 these exumbrella cirri are still con- 

 nected with the ring-canal by nar- 

 row peronial strands, but these are 

 often obliterated. There are 8 adrad- 

 ial, open lithocyst-sacs, but Hart- 

 laub was unable to determine the 

 number of concretions, but Gosse, 

 1853, who seems to have observed 

 this medusa, states in his "Natural- 

 ist's Rambles on the Devonshire 

 Coast" that there are 35 to 50 in each 

 sac, but Brown, 1896, finds only 12. There are no excretion papillae and no marginal 

 warts, and the velum is quite broad. 4 narrow, straight radial-canals. Stomach small, 

 4-sided, and with 4 well-developed, folded lips. 4 perradial, ciliated furrows in the exumbrella 

 floor of the stomach. The 4 narrow linear gonads are upon the radial-canals leaving both ends 

 free. Stomach and gonads reddish-purple, tentacle-bulbs purple with yellow center. 



Gosse found that when this medusa was disturbed by touching it with a stick at night the 

 ocellus-like spots above its tentacle-bulbs glowed suddenly with great brilliancy. Northern 

 coasts ot Europe, England to Norway. 



Subfamily PHIALINjE. 

 Eucopidae with other than 8 lithocysts; manubrium with a short flaring peduncle. 



Genus CLYTIA Lamouroux, 181 2, in part, sens. Hincks, 1868. 



Clytia, LAMOirROux, 1812, Nouv. Bull, des Sci. par la Soc. philomantique, tome 3, annee 5, No. 63, p. 184; 1816, Hist, des Poly- 

 piers coralligenes, Caen, p. 202. — Agassiz, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 354. — Agassiz, A., 1865, North 

 Amer. Acal., p. 78. — Van Beneden, 1866, Fauna Littoral de Belg., p. 165. — Hincks, 1868, British Hydroid Zoo- 

 phytes, vol. 1, p. 140. — Bedot, 1901, Revue Suisse de Zool., tome 9, p. 436; Ibid., 1905, tome 13, p. 60. 



Eucope (in part), Gegenbaur, 1856, Zeit. fiir wissen. Zool., Bd. 8, p. 241 (young medusae). 



Epenihesis, McCradv, 1857, Gymn. Charleston Harbor, p. 191. — Haeckel, 1879, Syst. der Medusen, p. 182. — Browne, 1896, 

 Proc. Zool. Soc. London, p. 487. 



Fin. 134a. — Cosmerira pilosella, after Hartlaub, in Zool. Anzeiger. 



