THE GENUS POLYSIPHONIA. ` 311 
Fig. 33. P. obscura. Habit drawing. 
34. » X T. S. of thallus. 
35. " Portion of thallus bearing attachment organs. 
36. P.opaca. Habit drawing. (Herb. spec.) 
37. ” T. S. of thallus. 
38. P. simulans. Habit drawing. 
39. » T.S. of thallus. 
40, » Portion of thallus showing attachment organs. 
41. P. subulifera. T. S. of thallus. 
42. » Habit drawing. 
43, P. elongella. Habit drawing. 
44. » Exterior view of attachment organ. 
45. » T. S. of thallus. 
PLATE 24. 
Fig. 46. P. elongata. Habit drawing. (Winter state.) 
47. » Longitudinal section of thallus showing attachment organ. 
48. > Portion showing ramuli. (Summer state.) 
49. " T. 8. of thallus. 
50. P. Richardsoni. (From Dr. Richardson's specimen, Nat. Hist. Mus.) 
51. P. fibrata. Portion of thallus showing attachment organs. 
52. " Habit drawing. 
53. » T. S. of thallus. 
54. P. fibrillosa. Habit drawing of plant on Rytiphlæa pinastroides. 
55. " L.S. of attachment organ grasping thallus of Ryriphlea pinastroides. 
56. » T. S. of thallus. 
57. P. violacea. Habit drawing of plant on Chorda filum. 
58. » T. S. of thallus. 
59. » L. S. of thallus showing attachment organ. 
60. P. spinulosa. (From herb. spec. Nat, Hist. Mus.) 
61. P. Brodwei. T.S. of thallus. 
62, » Portion showing attachment organ. 
63. " Habit drawing. 
PLATE 25. 
Fig. 64. P. fœtidissima, Attachment organs when growing on Codium adherens. 
65. " Habit drawing. 
66. » T. S. of thallus. 
67. P. nigrescens, Habit drawing. 
68. » T. S. of thallus. 
69. » Branch bearing tetraspores. 
70. " Portion showing attachnient organ. 
71. » Cystocarp with carpospores, 
79. » Interlocking attachment discs seen from below. 
73. P. nigrescens var. affinis. Habit drawing. 
74. P. variegata. Habit drawing from herbarium specimen of Rev. W. S. Hore. 
79. » Portion showing attachment organ. 
76, n T. S. of thallus. 
77. P. fruticulosa. Habit drawing of plant on Corallina officinalis, 
78. » Portion showing attachment organs. 
79. » T. S. of thallus, 
