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



Genus 57. Stephanospira, 1 Gegenbaur, 1859. 

 Stephanospira, Gegenbaur, Neue Beitrage, &c, 10, p. 67, figs. 53-58. 



Definition. — Discolabidee with a ruultiserial nectosome, composed of several rows of 

 nectophores spirally arranged. (Siphosome with a single corona of palpons.) 



The genus Stephanospira was established in 1859 by Gegenbaur for a Physophorid 

 of unknown origin, of which he could only examine a single incomplete specimen, 

 preserved in alcohol ; the nectophores as well as the siphons and palpons were detached 

 and lost ; the trunk only was preserved, with the pneumatophore at the apex and the 

 corona of gonodendra in the periphery of the siphosome. It is, therefore, easy to explain 

 that the description of Gegenbaur contained some errors, and that he supposed it to be 

 a widely aberrant type of Pkysophoridaa. Sars has since corrected those errors, and 

 made it probable that Stephanospira may be only a mutilated specimen of Physo- 

 phora (27, Heft iii. p. 42). The same opinion is supported by Claus (74, p. 16, &c). 

 Indeed, it may be that this opinion is right, and in any case Stephanospira belongs to 

 our family Discolabidae. But the incomplete state of the single specimen examined, 

 which it is impossible to identify, and mainly the entire absence of nectophores, leaves 

 open the question, whether these were arranged originally in two opposite, four cruciate, 

 or numerous spiral rows. Having recently seen an excellent picture by Mr. Wild, taken 

 from life, representing an Atlantic Physophora, the conical nectosome of which is 

 similar to that of Forskalia and composed of numerous nectophores spirally arranged, I 

 retain for this form the name Stephanospira. I shall pubbsh the description and figures 

 of this Step>hanospira corona in my Morphology of the Siphonophorae. In form the 

 vesicular spiral trunk and the distinctly ordinate monoclinic pairs of gonodendra are 

 similar to those of Stephanospira insignis, Gegenbaur. 



Family XVII. Anthophysid^e, Brandt, 1835. 



Anthophysidx, Brandt, 1835, Prodromus, &c, 25, p. 35. 

 Athorybidm, Huxley, 1859, 9, pp. 71, 85. 



Definition. — Physonectoa polygastricse, with a short vesicular stem of the siphosome, 

 bearing numerous siphons and palpons, each siphon provided with a branched tentacle. 

 Nectosome without nectophores, but with a corona of bracts. Pneumatophore with 

 radial pouches. 



The family Anthophysidse of Brandt (1835), identical with the Athorybida) of 

 Huxley (1859), differs from all the other Physonectse polygastricse in the absence 

 of nectophores, which are replaced by a corona of bracts. It agrees in this striking 



1 Stephanospira = Spiral corona, <m ?«»<>?, (ramjet. 



