40 GEEYONOPSIS DELICATULA. 



short tentacula, numerous (16x4+4), but not placed in contact, and irregularly developed. 

 They are of a shghtly milky hue, and have slightly bulbous bases, but no coloured ocelli. 

 There appears to be an otolitic mass in the cavity of each bulb, but I could observe no motion 

 The sub-umbrella is hemispherical and depressed ; down it run four simple vessels to join the 

 marginal vessels, and in their course are four greenish conspicuous, linear-lanceolate, or 

 rather claviform, reproductive glands, with wavy margins. Round the inner margin of the 

 umbrella is a horizontal, broad, membranous veil or shelf. From the summit of the sub- 

 umbrella depends a conical peduncle, which projects beyond the margin, and, after contracting, 

 suddenly expands into a wide campanulate stomach, with four large, lanceolate, fimbriated 

 lips, whose edges are bordered by a thick layer of fibrous cells, endowing them with a highly 

 motor power. Into the summit of the cavity of the stomach the four gastric vessels are plainly 

 seen opening. The lips are tinged with green. The disk measures one inch and a half across. 



Several specimens occurred on the coasts of Dorset and Devon during August 1836, 

 especially in the Reach of Dartmouth. It was usually in company with the Geryonia 

 appendiculata. 



In 1839, Professor Goodsir and I took a Medusa at Scalloway, in Zetland, presenting 

 many of the characters of the species we have described, but differing in having much longer 

 and more numerous tentacula, more clavate and purple ovaries, and pale fimbriated lips. We 

 announced it at the meeting of the British Association, at Birmingham, as a new Oceania, and 

 it has since been quoted as such by Lesson. For the present, however, it is better to abstain 

 from naming it, though in all probability distinct, since the drawing and memoranda made at 

 the time are insufficient ; the animal, owing to unavoidable circumstances, not having been 

 submitted to microscopic observation. I may here remark, once for all, that under no circum- 

 stances can any of the naked-eyed Medusae (above all, those belonging to the tribe we are now 

 treating of) be identified without aid of the microscope, and the accident of that instrument 

 not having been employed for the examination of Acalephse by the greater number of 

 zoologists who have written upon them systematically, has rendered published diagnoses and 

 determinations so imperfect, as, in the majority of instances, to be little better than utterly 

 worthless. The quoting of authorities, sjoionyms, and localities respecting the subjects of 

 this monograph is, in fact, an act of courtesy to those who have gone before us, rather than 

 of justice to science, which would have thriven better if half the bad figures and worse 

 descriptions of the smaller Medusae had never seen the light. Too truly in this case might it 

 be said of such describers — 



" They have perplexed. 

 With a dark comment. Beauty's clearest text ; 

 They have not told her face's story true. 

 But brought false copies to our jealous view." Cakew. 



Of course, there are some honorable exceptions to this censure, especially Sars, Wagner, Milne 

 Edwards, and Will. 



The higher Medusae, probably because larger, have been more fortunate. The 

 Geryonia pellucida of Will (Horse Tergestinse, p. 70, pi. 2,'-f. 8) is a Geryonopsis not far 

 removed from the species before us. It differs in having more clavate ovaries, simpler lips, 

 and finer marginal tentacula (64). Dr. Will relates of his species that it devoured eggs of 

 Beroe rufescens, of which some living specimens kept in the same vessel had laid many eggs, 



