OCTACTINIA. 
523 
“ Greenland (viz., Spitzbergen !) in 236 fath. Generative products were 
not found in any of the polyps of either kind. The characters given by 
Lindahl (8) must be modified, inasmuch as Kolliker’s (6) U. thomsoni (pp. 
5-11, pi. i. figs. 1-5) has dorsal zooids and spicules in the sarcosome. The 
two specimens were found in 2125 fath., between Portugal and Madeira, 
during the “ Challenger ” expedition. Kolliker also discovered the sexual 
organs, which are fixed to four of the septa in the basal part of the polype. 
Lindahl’s two species are only based on characters of age and different 
degrees of contraction of the soft parts ; Kolliker therefore unites them 
as U. UndaJili (which may however possibly be identical with U. en- 
crinuSj L.) ; and gives the character of the genus and family thus: — Pen- 
natnle(n with a long thin stem and a short thick polype -bearer, with 
strongly-pronounced bilateral symmetry on the ventral aspect ; polypes 
very large, sessile, without calycles, not retractile, placed in lateral rows 
to the left and right on the dorsal aspect of the keel ; also a terminal 
polype ; sexual organs in the lowermost portion of the polypes, on four 
septa ; zooids between and at the sides of the polypes, ventral, lateral or 
dorsal, leaving the ventral median line free ; axis quadrangular, with 
rounded angles and four profound furrows. 
A note by A. E. Verrill, Am. J. Sci. (3) vii. p. 70, accompanying the 
reprint of R. E. C. Steam’s second paper on Verrilia hlahii [c/l Zool. 
Rec. X. p. 508], intimates that this genus is most nearly allied to 
Halipteris christi (K. D.), and probably should be referred to the same 
genus. The characters of the sub- genus Verrilia are given thus (10) : — 
Polypidom linear-elongate, round, oval or ovate in cross section ; axis 
round, slender, bony; polypes arranged iii two unilateral longi- 
tudinal series ; there are four largo lougitiidinal canals in the basal 
portion of the stem ; in the polypiferous portion, these are rudimentary, 
with the exception of the one turning towards the polypiferous wing- 
like dilatation of the sarcosome. 
Heteroxenia, g. n., Kolliker (6). Habit and structure of Xenia ; polypes 
not retractile, on the terminal disc of a thick fleshy stem, dimorphic ; 
sexual polypes large, placed somewhat apart, those on the rim of the 
disc smaller ; tentacles one-quarter or one-half longer than the body, with 
four rows of pinnulse on each side ; zooids much more numerous, filling 
all the intervals between the true polypes, freely prominent, cylindrical, 
mouth with four simple and very short tentacles ; calcareous spicules as 
in Xenia^ rarer in the interior of the stem, crowded in the endoderm of 
both kinds of polypes. H. elizahethce, sp. n., id. 1. c. pp. 12-17j pi. ii. 
figs. 7 & 8 (Port Denison). There is also a species of Heteroxenia in the 
Red Sea, but Xenia umhellata^ Sav., ccerulea, Ehrbg., and Ccespitularia 
multipinnata, Val., are true (not dimorphic) Xenice. 
Sijdionogorgia, g. n., id. 1. c. Type of a new sub-family, between the 
Gorgoniidce and A Icyoniidce^ with the habit of the former : sarcosome 
hard, formed of connective tissue and many calcareous spicules ; polypes 
retractile, with slightly prominent calycles, which only occur at the ends 
of the smaller branches ; intestinal cavities prolonged in the shape of 
channels, penetrating the whole polypary, in the interior of the stems 
and branches ; only four of the septa are continued into these tubes, viz.. 
