NO. 1 TAYLOR: PACIFIC MARINE ALGAE 179 



be mechanically eroded from the upper surface also, and smoothed to com- 

 paratively uniform level. Here the thickness of the vertical septa is seen 

 to be about 1.3-1.7 mm. The conceptacles are developed on the vertical 

 portions as well as on the horizontal ones of this plant. They are most 

 abundant on that side of the chamber which faces toward the outer margin 

 of the plant, but probably not so abundant there as on the horizontal 

 portion. They are about 450-570 /a diam., very little elevated, with a very 

 small central pore; when decorticated the cavity appears to be about 300- 

 450 fi diam. 



Ecuador : Archipielago de Colon, horizontal-stage plants with a few 

 erect projections occasional near low tide line, Tagus Cove, I. Isabela, 

 no. 34-176, 13 Jan. 1934. Ibid., abundant plants in all stages of devel- 

 opment near low tide line in the surf on rocks. Black Beach Anchorage, 

 I. Santa Maria, no. 34-233, 17 Jan. 1934. Ibid,, horizontal-stage plants 

 occasional near low tide line on an islet in Gardner Bay, I. Espanola, 

 no.J^-^Ji,31 Jan. 1934. 



Lithophyllum divaricatum Lemoine ? 



Lemoine 1929, p. 63, pi. 2, fig. 6. 



Mexico: Is. Revilla Gigedo, rare as dredged from 36 meters at sta. 

 132, Braithwaite Bay, I. Soccoro, no. 34-37B, 2 Jan. 1934. Guerrero, 

 rare as dredged from 18 meters' depth at Ba. Petatlan, no. 34-584B, 2 

 Mar. 1934. Panama: washed up on shore, I. Jicarita, no. 34-507 A, 20 

 Mar. 1934. Ecuador: Archipielago de Colon, Lemoine loc. cit. 



Lithophyllum bracchiatum (Heydrich) Lemoine 



Heydrich 1901, p. 531 (as L. lithophylloides f. bracchiata) ; Lemoine 

 1929, p. 44, pi. 4, fig. 5 (as L. brachiatum) . 



Mexico : Is. Revilla Gigedo, abundant from lower tide pools along 

 the shore of Sulphur Bay, I. Clarion, no. 39-5, 16 Mar. 1939. Ibid., 

 intertidal at Braithwaite Bay, I. Soccoro, no. 34-9 (det. ?), 2 Jan. 1934. 

 Nayarit, from crevices in the surf zone, I. Maria Magdalena, Las Tres 

 Marias, no. 39-672, 9 May 1939. Panama: in tide pools exposed to 

 severe surf, Is. Secas, no. 39-121 (det. ?), 26 Mar. 1939. 



Lithophyllum frutescens (Foslie) Lemoine 



Lemoine 1929, p. 63, pi. 2, fig. 4. 



Reported from I. Santa Cruz and I. Santa Maria, Archipielago de 

 Colon. 



