SYSTEMATIC AND BIOLOGICAL ACCOUNT 129 



at the end of June 1949. I have watched the detached gonophores extruding eggs, and have also 

 observed the spent gonophores. My attempts to raise the polygastric generation from wild male and 

 female gonophores, kept in an improved Harvey rocker (see Rees & Russell, 1937), failed in my 1949 

 and 1950 experiments at Villefranche. I described and figured a very similar, if not the same, eudoxid 

 as Eudoxia russelli in 1932, from material brought back from the Great Barrier Reef of Australia. 

 It occurred there on 20 September 1928 at one station at the Barrier Reef lagoon, and on 20 October 

 1928 at another station outside Trinity Opening. At these two stations the polygastric stages of both 

 Chelophyes appendiculata and Ch. contorta were present. In December 1948 Fraser-Brunner took 

 some more eudoxids off Aden, very similar to Eudoxia russelli in structure and associated with the 

 polygastric stages of Chelophyes contorta. Ch. appendiculata was very much less common in Fraser- 

 Brunner's catches, ten specimens in one catch against 359 of Ch. contorta in five. In the one catch 

 both specimens occurred. 



Using my 1932 terminology, the left sutural ridge of the eudoxid bract of Ch. appendiculata, taken 

 wild at Villefranche, does not bear such a marked crest as the right, and the left ridge terminates 

 before reaching the basal edge of the bract. Although a trivial character, this serves as a very useful 

 field-mark for distinguishing between eudoxids of Ch. appendiculata and Lensia conoidea when 

 breeding from wild eudoxids. Another such field-mark for use in the Mediterranean is the colour of 

 the tip of the manubrium of the gonophore of an eudoxid. It is yellow in L. subtilis and pink in three 

 species of Muggiaea. I have no written notes on the colour in Lensia conoidea or Chelophyes 

 appendiculata. 



Vogt (1854), a pioneer who made very valuable observations at Nice, figured three eudoxids of 

 unknown parentage whose nature he did not understand. He thought that they had developed from 

 eggs and that they would grow into polygastric specimens of his Galeolaria aurantiaca ( = Sulculeolaria 

 quadridentata). The largest one figured, without a mature gonophore, on his plate 21, probably presents 

 the eudoxid of Chelophyes appendiculata. 



Up to the present time, therefore, I think it fair to say that we have no detailed description or figure 

 of the full grown eudoxid of Ch. appendicidata except for Eudoxia campanula Leuckart (1853); 

 Diphyes sieboldii Moser (1925, pi. xn, fig. 8 — an eudoxid caught at Villefranche); and Eudoxia russelli 

 Totton (1932). 



A Mediterranean calycophore whose eudoxids might be mistaken for those of Chelophyes appendicu- 

 lata is Lensia conoidea (referred to by Moser and also Leloup as Galetta truncata). But it is much 

 larger and the bract lacks the distinct cavity found in Eudoxia campanula and E. russelli, and the 

 gonophore has a truncate articulating end, as in most species of Lensia. 



There remains the task of differentiating between the eudoxids of Chelophyes appendiculata and 

 Ch. contorta, which species were taken together, both by ' Mabahiss ' and ' Discovery II ' in the Indian 

 Ocean. 



The length of a free swimming, mature, male gonophore of Ch. appendiculata taken at Villefranche 

 (28 March 1949) was found to be 4-5 mm. A full-grown bract measured about 2-5 mm. in length and 

 1-25 mm. in (maximum) diameter. 



Observations on the behaviour of this very rapidly swimming species were made by me at 

 Villefranche. When a complete, living, polygastric specimen sinks in a container of water it does 

 so with its main axis vertical. The small posterior nectophore only is used to maintain vertical 

 height, and contracts feebly at intervals to do so. The animal also cruises about slowly in a horizontal 

 position in the same way without contracting its larger anterior nectophore until the high-speed 

 'escape action ' is called for, when the anterior nectophore comes into use. It was not possible to see 

 what the posterior nectophore was doing when the animal was travelling at speed. 



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