124 THE PLUMULARID^E. 



the liydrotbeca; orifice terminal, and continuing downward on the side facing the hydrotheca; 

 cauline nematophores very large, ' variable in form, two on eacb internode, more or less triangular, 

 rounded, or with one of tbe upper corners greatly produced, tapering toward the base; the external 

 orifice is very large, extending entirely across tbe upper margin and into the lateral processes 

 when the latter exist; tbe opening from the cavity of the nematophore into tbe stem is also very 

 large, often being equal in size to tbe internal orifice of the hydrotbeca'. At tbe base of each 

 pinna in a direct line with tbe liydrotbeca' is an oval swollen process, with a small circular orifice 

 on the upper surface near the proximal end; its cavity is distinctly continuous with that of tbe 

 liydrotbeca in front of it, and also with that of the stem." 1 



Gonosome. Unknown. 



Distribution. lilnke, lat. N. 24 OS', long. W. 82 51'; depth, 339 fathoms. 



TI/I>I: In the Museum of Comparative Zoology, Cambridge, Massachusetts. 



LYTOCARPUS CLARKEI, new species. 

 (Plate XXXII, figs. r>-7.) 



Trophosome. Colony rather profusely branched in an alternate manner, rigid, very dark 

 colored when fresh, attaining a height of 12 to 14 inches; stem fascicled throughout; the branches, 

 branchlets, and hydrocladia springing from the anterior tube only; hydrocladia alternate, divided 

 into regular iuternodes, each of which has a very strong bori/.ontal scptal ridge opposite tbe 

 intratbecal ridge, and sometimes another inconspicuous oblique ridge opposite the supracalyciue 

 nematopbores; liydrotbeca' rather closely approximated, ovate in outline, tbe margin usually 

 tlaring very slightly; marginal teeth seven in number, rounded, often incurved; iutrathecal ridge 

 conspicuous, horizontal, reaching across the hydrotheea; supracalycine nematophores varying in 

 length, usually slightly overtopping the hydrotheea, and sometimes nearly as long as in L. gramlis; 

 mesial nematopbore not attaining the level of the top of the bydrotheca; distal portion free and 

 distinctly separated from the liydrotbeca, which has a round opening just above its junction with 

 tbe mesial nematophore; cauline nematophores very large, two to each internode of the stem, one 

 triangular in outline, and the other with one corner produced into a long, spurlike projection; 

 there is a perforated process on tbe base of eacb bydrocladium. 



Goiiosome. Gonangia borne on modified hydrocladia, which are aggregated together to form 

 a pseudo-corbula; the distal portion of the branch giving off ordinary alternate hydrocladia. 2 



Distribution. Albatross Station 2162, lat. N. 23 11', long. W. S2 > 20'; depth, 122 fathoms; 

 Albatross Station 2164, lat. N. 23 11', long. W. 82 20'; depth, 192 fathoms: Albatross Station 2167, 

 lat. M.23 11', long. W. 82^ 21'; depth, 201 fathoms; Albatross Station 2169, lat. N. 23 10', long. 

 W. 82 20'; depth, 78 fathoms; Albatross Station 2330, lat. N. 23 11', long. W. 82 19'; depth, 

 121 fathoms ;rAZ6<ross Station 2331, lafc.K 23 11', long. W.8220'; depth, 114 fathoms; Albatross 

 Station 2334, lat. N. 23 11', long. W. 82 18'; depth, 67 fathoms; Albatross Station 2336, lat. N. 

 23 11', long. W. 82 19'; depth, 157 fathoms; Albatross Station 2337, lat. N. 23 11', long. 82 20'; 

 depth, 199 fathoms; Albatross Station 2338, lat. 23 11', long. W. 82 20'; depth, 189 fathoms; 

 Albatross Station 2365, lat. N. 22 "-' 18', long. W. 87 04'; depth, 24 fathoms. State University of 

 Iowa expedition; oft' Little Cat Island, Bahamas, 13 fathoms. 



This species comes very near to L. i/nnulis, but it differs constantly in the fact that the mesial 

 nematopbore does not attain the level of the top of tbe bydrotheca, and has its distal end free. 

 Specimens from shallow water, near Little Cat Island, Bahamas, arc more rigid than tbe others, 

 and have the ctenosarc crowded full of black pigment cells of some sort, while others do not 

 show so many of these granular bodies. The Albatross specimens from deeper water are not so 

 rigid, and have a straggling, irregular manner of branching. The specimen from Station 2167 is 

 very symmetrical and typical, and is the one having the gonosome. It was taken on May 1, 1884, 

 while most of the other . I llm/mss specimens were taken in June, 1885. The specimens from Little 

 Cat Island were dredged in June, 18!)."., and the gonosome was not present in any of them. 



Tyin nli,l,'s. Cat. No. 15400, Mus. State Univ. Iowa; Cat. No. 18698, U.S.N.M.; also in the 

 collection of the author. 



'From Doctor Cl;irkr's original description. 



-Fur details of this interesting structure see the description of this genus. 



