>S. F. Clark — Hj/droids of the Pacific Coast, 261 



Plumularia setacea Lamarck. 



Sertularia piiinata, [3, Linn., Syst. Nat., 11! 12. 



Sertularia setacea Pallas, Elench., p. 148. 



Plumularia setacea Lamk.. An. s. Vert. (2d ed.), ii, 165. 



Plate XLI, figures 1, 2. 



Stems simple, slender, erect, rooted by a creeping stolon and 

 divided by transverse joints into short internodes of uniform size, 

 regularly branched ; pinn.e alternate, regulai-ly arranged, one from 

 each internode, arising from the stem by a pi-ominent process pro- 

 duced from the outer and upper side of each internode, divided by trans- 

 verse or slightly oblique joints into internodes of two sizes arranged 

 alternately. In large specimens 150"'"'. to 800'""'. long, the main stems 

 are considerably branched, the branches alternately arranged and 

 clustered, extending quite or nearly to the distal end of the stem; 

 the branches give off" l)ranchlets, which like themselves resemble the 

 main stems in every particular. Hydrotheca? with an even rim, small, 

 borne on the larger sized internodes of the pinna>. Nematophores 

 compound, those on the pinn;v not quite equal in length to the hydro- 

 thecfe, those on the main stems a little longer than the hydrothecae; 

 three on each internode of the stem, two in the axil of each pinna, 

 one on the opposite side of the internode near the bnse, one only on 

 the upper side of the smaller joints of the pinn{\3 and three on the- 

 larger joints, one just below the hydrotheca, and one on each side of 

 the apertui-e Gonotheca^ sessile, l)orne in the axils of the pinna* ; 

 female elongate oval, produced at the distal end into a tubular neck 

 with a discoidal, terminal orifice ; male, smaller than the female, 

 fusiform, and with a much smaller aperture. 



Santa Cruz, Cal., — C. W. Anderson; San Diego, Cal, — Dr. H Pal- 

 mer; San Diego, Cal., — H. Hemphill; Vancouver Island, — Dawson. 



Most of our specimens consist of dense clusters of the delicate 

 shoots, about 50'""'' to 80"""* long, and usually attached to some large, 

 coarse alga. Ellis' old name of " iSea Bristle.^'''' was well chosen, for 

 it conveys quite an accurate idea of the appearance of these smaller 

 forms. The larger forms are more branched, usually of a darker 

 color and have a closer resemblance to hair than to bristles; one of 

 our largest specimens from San Diego consists of a tuft 200"""- in 

 length composed of about three hundred branched shoots ; this liad 

 been washed ashore and was found by Dr. Palmer; a still larger 

 specimen was dredged off San Diego in six to ten fathoms by IVIr. 

 Hemphill, which measures .300"""- in length and forms a thick cluster 

 of about a thousand shoots. 



