396 W. K. BROOKS ON THE LIFE-HISTORY 



The species is very abundant at Beaufort in August and September, and it is usually 

 found in company with Liriope, scutigera, to which it bears a close superficial resem- 

 blance which may possibly be due to mimicry. This resemblance led Eschscholtz to 

 associate these and allied medusas with the Geryonidse and it is expressed by the name 

 Geryonopsida? proposed by Agassiz for the Eutimidas, Eirenida3 and related medusae. 



Ontogeny. I have reared the hydroid from the egg laid by the medusa. It is a 

 Campanopsis very similar to the one from which Glaus obtained the young medusas of 

 Octorcliis (Eutima) Gegenbauri. It has a prominent, rounded manubrium, a single circ- 

 let of ten tentacles, arranged in two alternating series, and an elongated cylindrical body, 

 which is not covered by the perisarc which invests the unannulatcd stem, PL 38, fig. 10. 



Eutima variabilis, McCrady. 



PI. 39, fig. 1 ; PI. 40. 



Eutima variabilis, McCrady, 1857. Gymnophthalmata of Charleston Harbor, p. 88. 

 L. Agassiz, 1862. Contributions IV, p. 363. 

 A. Agassiz, 1865. N. A. Acalephre, p. 116. 

 Octorchandra variabilis, Haeckel, 1877. Prodrom. System Med., Nr. 211. 



Haeckel, 1879. System der Medusen, p. 199. 

 Eutima sp., Brooks, Studies Biol. Lab. 1882. 



Species-Diagnosis. Umbrella thick, flattened, more than three times as wide as high 

 Peduncle about equal in length to radius of bell, and less than twice as long as its 

 height. Stomach short, quadrate, much folded, and prolonged into four pointed, crenu- 

 lated lips. Sixteen tentacles of equal length, with three or four marginal thickenings 

 between adjacent tentacles. Eight marginal bodies with ten or twelve otoliths in each; 

 the medium one largest and the others in pairs. Each marginal vesicle lies close to 

 radial sides of bulb of tentacle next radial tentacle. Reproductive organs usually 

 divided into a sub-umbral and a peduncular portion ; the latter absent in the young. 

 No marginal cirri or accessory tentacles. 



Color. Umbrella and peduncle transparent and colorless. Stomach and endoderm 

 of tentacular bulbs intense green by reflected light. Endoderm of tentacular bulbs 

 bright pink, and ectoderm sky-blue by transmitted light. Ectoderm of tentacular bulbs 

 colorless by reflected light. 



Size. Diameter of bell about 30 mm. Height about 7 mm. 



Habitat. Charleston, S. C, McCrady ; Beaufort, N. C, Brooks. It is a rare species 

 at Beaufort and most of the specimens which I obtained were captured outside in 

 August and September. 



Ontogeny. Although I obtained ripe eggs on several occasions they were not fer- 

 tilized and we have no direct knowledge of the ontogeny, although there is no reason 

 to suppose that the hydra is different from that of Octorcliis {Eutima) Gegenbauri and 

 Eutima mira. 



Remarks. McCrady's specimens had only twelve tentacles, while all the mature 

 specimens which I obtained had sixteen, but as the Beaufort specimens agree with his 

 description in all other respects, their identity can hardly be doubted. The tentacles 



