101 





markets from Monterey, Tomales Point, Punt a 

 Keys, and old shells, Bay of San Francisco. 



6'. f areata. Trask. Plate 5, fig. 2, a. b. c. 

 d. c. — Polypidom long, four to nine inches, adnate 

 to the various marine alga; on which it grows, 

 and often quite embeded in the fronds of marine 

 plants, pinnated, color corneous ; rachis cylin- 

 drical, jointed ; the pinnae are simple and for the 

 most part free, arising from the lower portion of 

 the joints of the rachis. Their attachment to the 

 main stem is somewhat peculiar ; for, like the 

 rest of the members of this genus, they are not 

 given off from the main stem by a fixed joint, 

 but have their origin from the end of a sessile 

 pedicel ; this is attached to the rachis by a strong 

 base, is sub-pyriform and cylindrical, is free for 

 about three-fourths its length, terminating in a 

 rather bluntly-rounded rostrate process en the 

 outer and superior aspect. 



From this pedicel the pinna; arise by a flexible 

 joint, allowing a latitude of motion indicated be- 

 tween their attachment and the rostral end of 

 this process. Figure (a) represents two joints of 

 the rachis and its pedicels, with the pinna; ari- 

 sing therefrom as seen under a power of thirty 

 linear diameters. The cells are immersed in the 

 pinna; for about two-thirds their length, opposite, 

 two upon each joint, compressed, the superior 

 ends considerably divergent, acutely sinuatcd on 

 the upper and outer edge, as seen in jig. 2, c. d, 

 they are a little in front of the lateral line. A 

 back view is shown at fig. b. 



The ovarian vessicles are produced from the 

 lateral and back part of the pinna; at the base of 

 the cell, are sessile, of a light corneous color, pol- 

 ished, and have an elongated oval form, some- 

 what swelling on the outer side, with a large 

 oval mouth, the edges of which are somewhat de- 

 pressed below the summit. 



It is not without some doubts that I have 

 placed this zoophyte in this genus, believing that 

 there are sufficient distinctions in the species to 

 form a new generic type ; but as no opportunity 

 has offered to observe its habits, and nothing is 

 at present known regarding the animal, it is 

 thought best to place it provisionally in this ge- 

 nus for the present, until farther opportunities 

 shall offer for its investigation. 



Bay of San Francisco and Farrallone Islands. 



S. turgida. Trask. Plate 4, fig. 1.— Poly- 

 pidom erect, from two to three inches high, pin- 

 nated, color corneous, at times it is found aduate 

 to substances on which it grows ; pinna; arise al- 

 ternately from opposite sides, jointed, compressed; 

 cells lattro-frontal, alternate, one on each joint, 

 and situated above the middle, are free for near- 

 ly three-fourths their length, divergent, sub- 

 eylhidhcal, round, full, with a broad aperture 

 which is somewhat constricted below the edges ; 

 the upper and outer edge is deeply sinuatcd, thus 

 forming two rather large denticulations more or 

 less rounded, but occasionally one or both are 

 found sub-acute. This peculiarity is often met 

 with in adjoining cells on the same pinna;. The 

 inner edge of the aperture is slightly everted, 

 and rather more deeply constricted than the out- 

 er or lateral portions, and forms a broadly round- 

 ed margin with a slightly raised lip. 



The ovarian veflflicles arise from the back part 

 of the pinna?, sessile, large, sub-pyriform, the 



upper half armed with stout, rounded, blunt, 

 spines, twenty to twenty- eight in number ; 

 mouth sub-cylindrical, the edges surrounded 

 with ten to fifteen smaller spines. The whole 

 polypidom presents a full, turgid appearance, 

 and is more or less marked with fine wrinkles, 



Bay of San Francisco, Monterey, Tomales 

 Point. On mollusca and alga;. Rather rare. 



Genus Plumularia (Lam.) 



Plumularia Franciscana. Trask. Plate 4, 

 fig. 3. — Polypidom six to eight inches high, 

 color corneous, alternately branched, the branch- 

 es pinnated, one branch to each internode of the 

 stem. The pinna; rise one above the other, are 

 pointed, and support three cells at each joint. — 

 On two specimens four cells have been met with, 

 but may be regarded an exception rather than 

 otherwise. The pinna; are dictotomously branched 

 in adult specimens. Cells lagenculate, smooth, 

 free, slightly decumbent; the attachment of the 

 base is marked by a slightly elevated rounded 

 rim, apertures round and smooth. 



Bay of San Francisco, among rejectamenta of 

 the beach. 



Genus Crisidia (M. Edw.) 

 Crisidia gracilis. Trask. Plate 5, fig. 3. — 

 Polypidom confervoid, very slender, branched, 

 calcareous, growing in little tufts from one- 

 fourth to a half inch in height; each cell is 

 jointed, flexible, and dark brown or black. Cells 

 cylindrical, free, the upper fourth divergent, in 

 some specimens slightly curved, the upper cell 

 given off from above the middle of the one be- 

 low it, and which becomes somewhat incrassate 

 at that point. Apertures round, smooth, facing 

 more or less alternate, surface smooth and shi- 

 ning. Sparingly found, attached to other zoo- 

 phytes and marine plants. 



Bay of San Francisco, Monterey, Punta Keys. 



Genus Crisia (Lamx.) 



Crisia occidentalis. Trask. Plate 5. fig. 4. 

 Polypidon erect, not exceeding one inch in 

 height, calcareous, irregularly branched, joints 

 dark and flexible. Cells tubular, slightly com- 

 pressed and diminishing in size from above 

 downward, lateral, from seven to nine on each 

 internode of the joints, alternate, surface finely 

 granulated, a high and sharply-rounded process 

 extending laterally and upward from the edge 

 of the aperture, and covered with a thin calca- 

 reous operculum, which is apparently sessile, and 

 somewhat excavated on its upper surface. Ap- 

 ertures a little ovate, with smooth edges and 

 slightly oblique. 



This species is closely allsed to C. eburnea, 

 (Johnston,) and would easily be mistaken for 

 that species on a mere casual examination. — 

 May not Mr. Thomson's spcoimen from Califor- 

 nia, which he thinks identical with C. eburnea, 

 have been an imperfect form of C. occidentalis 1 

 (vide Johnston's Zooph., 2d ed., page 281.)— 

 There are sufficient differences hi C. occidentalis 

 to separate it from C. eburnea, as may be seen by 

 an inspection of the figure, notwithstanding there 

 is a close alliance in many particulars. My 

 figure is drawn with camera lucidla undci a 

 power of thirty linear diameters. 



Attached to marine alga; from Santa Barbara 



