HYDROMEDUSAE, SIPHONOPHORES, AND CTENOPHORES. 299 

 EUTIMA LEVUKA (Agassiz and Mayer) Maas. 



Eutimeta levuka Agassiz and Mayer, 1899. p. 163, pi. 9, figs. 30, 31. 

 Eutimeta lactea Bigelow, 1904, p. 253, pi. 2, figs. 7, 8. 

 Eutima lactea Mayer, 1910, p. 300. 



Eutima levuka var. ocellata Maas, 1905, p. 35, pi. 7, figs. 43, 44. 

 V Eutima levuka Bigelow, 1909a, p. 165, pi. 5, figs. 2, 3; pi. 35, figs. 1, 2. 

 — Mayer 1910, p. 301. 

 ? Octorcliandra orientalis Hartlaub, 1909, p. 456, pi. 20, figs. 1-5. 



Eutima levuka — material examined. 



The number and arrangement of tentacular structures is as fol- 

 lows: 



SPECIMEN 9 MM. IN DIAMETER. 



Tentacles, series 1 . 



II 



III 



IV 



Tentacles, series 2. 

 Tentacular knobs.. 



1 

 10,14 



1 



14,11 



1 

 12,11 



1 

 13,14 



SPECIMEN 10 MM. IN DIAMETER. 



Tentacles, series 1 1 



II 



III IV 



Tentacles, series 2. 

 Tentacular knobs. . 



2 

 7,5,12 



2 

 12,6,7 



2 

 11,3,11 



1 

 11,12 



Thus the smaller specimen has 8, the larger 11 tentacles, and 99 

 and 97 knobs, respectively. 



Maas (1905, p. 35) has pointed out that the tentacles do not in- 

 crease regularly in number with development. My small specimens 

 from Acapulco had only four (Bigelow, 1909<z), while Maas records 

 large specimens with 4 to 6, and believes that the normal number is 

 8 — 4 peradial and 4 interradial. The large Philippine example 

 shows that 8 is not necessarily the final number, any more than it 

 is in specimens from the Atlantic (Apstein, 1913, records 4 to 21) ; 

 indeed, Maas has himself recorded small examples with more than 8. 

 But not enough specimens have yet been studied to show how great 

 the normal variation in number of tentacles may be in the Indo- 

 Pacific race. Various records have shown that the number of mar- 

 ginal bulbs to the quadrant is variable. The present specimens have 

 from 23 to 27. 



