138 



Papers from the Department of Marine Biology. 



List of Submerged Spermatophyles and Algce in the Gulf of Mexico about Tortixgas. 

 Order NAIADALES. ALG^E— continued. 



Cynwdocea manalorum Ascherson. 

 tee-arass. 



Mana- 



Order HYDROCHARITALES. 

 Family ELODEACEiE. 



Halophila engelmannii Ascherson. 

 Halophila baillonis Ascherson. 



Family Hydrocharitace^. 



Thalassia tesltulinum Koenig and Suns. 

 Turtle-grass. 



ALG^. 



CYANOPHYCEiE. 



Lyngbya majuscula (Dillwyn) Harvey. 

 Chlorophyce^. 



Caulerpa sertularioides (GmeUn) Howe. 



prolifera (Forskal) Lamarck. 



racemosa (Forskal) Agardh. var. 



occidentalis (J. Agardh.) Borgesen. 



ashmeadii Harvey. 



crassifolia (Agardh.) J. Agardh. 

 C odium tomentosum (Hudson) Stackhouse. 

 Penicillv^ dumetosits (Lamarck) Decaisne. 

 Udoteaflabellum (Ell. and Sol.) M. A. Howe. 

 cyathiformis (Decaisne) Howe. 



Chlorophyce.'E — continued . 



Halimeda simulans M. A. Howe. 



tuna (EUisandSolander) Lamarck 

 tridens (Ellis and Solander) La- 

 marck. 

 opuntia var. minor (Ellis and Sol- 

 ander) Lamarck. 

 Valonia ventricosa L. 



Dictyosphceria favtilosa (Agardh.) Decaisne. 

 Acetabidaria crenulata Lamaroux. 



Phjeophyce^. 



Diciyopteris justii Lamarck. 

 Zmiaria lobata A. K. Agardh. 

 Padina pavonia (L.) Gaillon. 

 Sargassuninatans (L.) Meyer — S. bacdferum. 



Rhodophyce^. 



Hypnea muscoformis (Wulfen) Lamarck. 

 Acanthophora spicifera Vahl, A. Ihierii 



Lamarck. 

 Lawrenda obtusa (Hudson) Lamarck. 

 Galaxaura flagelliformis Kjellman. 

 Wurdemannia setacea Harvey. 

 Corallina rubens L. 

 Gi'acillaria confervoides (L.) Greville. 



CONCLUSION. 



In this treatment of the species in the Tortiigas it has been aimed to 

 give some idea of the character of the dry-cUmate plants inhabiting 

 these islands, their distribution, and particularly the changes which 

 have occurred on the various keys since Lansing's survey, with an 

 attempt to analyze the reasons for such changes. This, it is hoped, has 

 been done, with the help of herbarium specimens collected and Uving 

 plants sent north to the University of Pennsylvania Botanical Garden, 

 and also the extensive field-notes and laboratory experiments made by 

 the writer during his residence of two summers in these islands. 



