138 THE VOYAGE OF H.M.S. CHALLENGER. 



Cymbonectes mainly in the complete infundibular cavity of the hydroecium, and, there- 

 fore, bears to it the same relation that Sphasronectes exhibits to Monophyes. 



Genus 23. Cymba, 1 Eschscholtz, 1829. 

 Cymba, Esch., System der Acaleplien, p. 133. 



Definition. — Monophyidse with an angular, pyramidal nectophore, and a complete in- 

 fundibular hydroecium on its ventral side. Bracts cuboidal, with six quadrangular faces, 

 and two lateral lobes arising from the base of the phyllocyst. 



The genus Cymba of Eschscholtz comprised in the system of its founder three 

 different species, the first of which [Cymba sagittata) belongs to a different genus of 

 Calyconectae (it is an Abylid). The second species, which I retain as the type of our 

 genus, is the Mediterranean Cymba enneagonum, Esch. ( = Enneagonum hyalinum, Quoy 

 et Gaimard, 2, pi. v. figs. 1-6). The monogastric generation, or the Eudoxia of this 

 polygastric Monophyid, is the third species of Eschscholtz, Cymba cuboides ( = Cuboides 

 vitreus, Quoy et Gaimard, not Huxley !). 



Different from this typical and oldest known Mediterranean form is a second, Austra- 

 lian, species, which Huxley described very accurately in 1859, under the name Abyla 

 vogtii (9, fig. 46, pi. ii. fig. 3). He rightly suspected that his Cuboides vitreus (not 

 identical with that of Quoy et Gaimard) might be the detached Eudoxia of the former ; 

 he found both together at the same place on the south coast of New Guinea. 



A third species, Cymba nacella, was found by me in 1881 in the Indian Ocean, and 

 will be described on another occasion. It is more similar to Cymba vogtii ( = Abyla 

 vogtii, Huxley) than to the two western species. Its Eudoxia is Cuboides nacella. 



The fourth species, here described as Cymba crystallus, was observed living by me 

 in the Canary Islands in 1867, and from these living specimens are taken the figures on 

 Pis. XLI. and XLII. (compare above, p. 111). The same form occurred in the Challenger 

 collection, having been taken in the Guinea current at Station 348. 



The remarkable cuboidal form of the bracts, and the bilobate horizontal diverticulum 

 of their phyllocyst, distinguishes Cymba at once from all other Calyconectae. 



Cymba crystallus, n. sp. (Pis. XLI., XLII.). 



Abyla crystallus, Haeckel, 18G7, MS. Canar. 



Habitat. — Tropical and Subtropical Atlantic, Station 348; April 9, 1876: lat. 

 3° 10' N., long. 14° 51' W. Surface. 



Canary Islands, Lanzerote, February 1867 (Haeckel). 



1 Cymba = Boat, xv/*ISri. 



