461 



66. Lithothamnion ruptile Foslie. 



67. occidentale Foslie. 



68. Lithophylluni accretuin (Fosl. et Howe) Lem. 



69. caribaeum Fosl. 



70. erosum Fosl. 



71. intermedium Fosl. 



72. daedalnm Fosl. et Howe. 



73. strictum (Fosl.) Lem. 



var. nana Fosl. et Howe. 



74. absimile Fosl. et Howe. 



75. (?) propinquum (Fosl.) 



76. prototypum Fosl. 



77. Melobesia farinosa Lamx. 



78. Chamaedoris Fosl. et Howe. 



79. atlantica (Fosl.) Lem. 



80. af finis (Fosl.) Lem. 



81. Porolithon mamillare (Harv.) Lem. 



var. occidentalis Fosl. 



82. Boergesenii (Fosl.) Lem. 



83. pachydermum Fosl. 



84. Arnphiroa rigida Lamx. 



85. fragilissima (L.) Lamx. 



86. Corallina cubensis (Mont.) Kiitz. 



87. Jania pumila Lamx. 



88. adhaerens Lamx. 



89. decussato-dichotoma Yendo. 



90. capillacea Harv. 



91. spec. 



* 



92. Sperniothamnion investiens (Crouan) Vickers. 

 var. cidaricola B0rgs. 



Besides the var. cidaricola (comp. p. 200), which covers the 

 spikes of Eucidaris tribuloides quite densely, I have come across 

 a closely related form which in a similar way may densely cover 

 the stems of Cham&doris Peniculum to which it is fastened firmly 

 by means of the numerous short rhizoids given off from the basal 

 creeping filaments (Fig. 422 a). The rhizoids are unicellular, end- 

 ing in a broad disc with coralliform outline. The creeping filaments 

 are upto 35 p thick. 



