TIIK .SKKTULAKIUJC. 133 



SELAGINOPSIS ALTERNITHECA i Levinsen ) 



(Plat.- XI., ti^. :> 7. 

 Tliiiinriii nil* riiitln -en LI:VI\SKX. Vi.l. Mc.l.l.-l. naliirh. l-'.nvn., ISHL'. p. :;i'. 



Trnji/iiixniii, . Colony attaining a height of about .". inches. Stein spirally twisted, very 

 thick and coarse, divided into long and irregular internodes. IVanehes springing from all sides 

 of the stem, dividing dichototnonslv sometimes three or four times, making a Habellate -t rin-t ure 

 resembling somewhat the branches of /'// ///<?//(/ //////'./. Nodes usually aliseni. except that there 

 is a sharp constriction al the liase of each liranch and hranchlet. Hydrothecffi very stout, much 

 liroadei 1 below than aliove, arranged in two rows on the sides of the- flattened branch. each row 

 thus occupying an edge of the liranch. the hvdrotheca- of a given row having their distal cuds 

 bent alternately to the right and left as in ////i/i-ii// in iiniii; margin without teeth, aperture round, 

 operculum a single abcauline flap. The top of one hydrotheca rises a little above the base of 

 the one next above. 



( i ininxiiiix . Gonangia borne on basal portions of branches, elongate oval, abruptly truncated 

 al distal end. with a very broad aperture and no neck. 



Distribution. l>avis Straits. IIHI fathoms (Levinsen). 



The aliove description of the main stem and manner of branching is taken from Levinsen's 

 account and (inures, tlie remainder being from a specimen (fragmentary) from the tvpe locality 

 kindly sent me bv 1'rofessor Levinsen. The specie.-, is a verv well marked one and looks like a 

 double llijdrtill am ii'ni . 



TI/JI, .v//./,x. Cat. No. I'.iso'.i, I'.S.N.M.; Cat. No. IsT::^, .Museum of (he Stale I'niversity 

 of Iowa; also in the collection of the author. 



SELAGINOPSIS HARTLAUBI, new species. 



i Plate X I., liu'. S. I 



Trophasome. -Colony in type specimen, which is incomplete, about 4.V inches high. Stem 

 divided into very lone; and irregular intcrnodes. Two rows of completely immersed hydrotheca'. 

 which do not have their distal portions inclined alternately to the right and left, are on opposite 

 sides of the stem. Mranches irregularly alternate, not ordinarily dividing into branehlets. 

 inlet-nodes long, divided from the very short processes of the stem by a deep constriction. 

 Ilydrotheca' in four TOW S, each of which resembles j,, arrangement those found in Hydrattmania, 

 where the distal cuds of the hydrotheca' are bent alternately to the right and left. Individual 

 hydrothcca- stout, tubular, completely immersed, with the distal ends much constricted: margin 

 oval, without teeth or angles. The bases of the hydrothecie in a given row are not in alignment, 

 as in llijili'nU iiiiinni. and in some places the alignment is so disturbed that the effect of eight. 

 instead of four, rows is produced. In places but two rows are visible in looking -it a branch 

 from above, and the hydrotheca' look is if implanted in pairs, the two of a pair having their 

 distal ends inclined the same way. as in tig. S. 



<iniiiixi>iiii>. Not known. 



I>;sii';i>iit!<ni.--Atl>ii1rtii<x Station ::.M;n, hit. N. .Ml 4u'. long. W. Iti'.i i'u'. depth 4:', fathoms. 



This remarkable hvdroid bears a curious resemblance to what might be called a " four ply" 

 IIii'li'iill niiin in. The type specimen is much damaged and overgrown with bryo/.oa. and 

 unfortunately lacks the gonosome. 



T;/j>. slides. Cat. No. I'.tsli', T.S.N.M.: Cat. No. Is7:'.r,. Museu ..... f the State t'niversity of 

 Iowa; also in the collection of the author. 



SYNTHECIUM Allman (modified). 



Ti'<'j>/itiKui,i, . Branches opposite, nodes regular. Hydrothecae opposite or alternate, margins 

 smooth, round, often rimmed or reduplicated. ( )perciilum apparently wanting. 



(iaiitixiniii . -Gonangia springing from the interior of liydrothecse, where thev replace 

 hvdranths. 



