Botanic Gardens
Kew Gardens: The world's first botanic gardens, and its evolution to a pre-eminent 21st century educational and conservation institution.
National Tropical Botanic Gardens: Lots of great pix with short, concise descriptions (links only with collaborating institutions)
Fairchild Tropical Botanic Garden: Great site, excellent photos of a wide range of tropical plants
Missouri Botanical Garden: A center for botanical research and science education, with a dynamic website
Cornell Plantations Botanic Gardens: A 14 garden Botanic Garden with an educational emphasis
North Carolina Botanical Garden: Part of The University of North Carolina at Chapel Hill, focusing on teaching and research, with a well organized website
Australian National Botanic Gardens: Plants, botany and horticulture with a profusion of images.
Pamela A. Campbell. Jamaica – Gardens by Nature and Design: Brief discussion of Jamaica’s Hope Gardens, the largest Botanic Gardens in the West Indies.
Friends of the Botanic Gardens of Trinidad and Tobago: Photographs and history of the Trinidad Gardens, together with the Constitution of its Friends.

Academic and Research Institutions
Images and Descriptions of Flowering Plant Families - Botany Dept, Univ. of Hawaii
Plants of Hawaii, USGS, Hawaii: A collection of images, maps, and reports of plants of Hawaii.
USDA Natural Resources Conservation Service: A very comprehensive plant database, including tropical plants of the US and its territories, with detailed descriptions and great photos.
Medicinal Plants of the Guianas by DeFilipps et al: Specifically the very comprehensive index of ailments and the plants used for treatment
Center for New Crops & Plant Products: A window to new and specialty crop profiles by Purdue University.
The UF/IFAS Center for Aquatic and Invasive Plants: A multidisciplinary research, teaching and extension unit of the University of Florida
The Miami Tree Puzzle: Quite comprehensive listing of the trees of Miami and environs, with excellent photos of trees, flowers and fruit.
Plants For A Future: A resource centre for rare and unusual plants, particularly those which have edible, medicinal or other uses.
Heliconia cultivars: an extensive photo gallery of exquisite Heliconia flowers taken by members and friends of the Heliconia Society of Puerto Rico (HSPR).
Plumeria in Hawaii by Richard Criley, provides a profusion of visually striking, exceptionally beautiful and vibrant Plumeria flowers in white, yellow, pink, red and every shade in-between.
Species Profiles for Pacific Island Agroforestry. A rich compendum of detailed descriptions and great photos of tropical Agroforest trees for extension agents and farmers. A great resource.

Commercial Sources
Floridata: A photo encyclopedia of tropical landscape plants, an online plant & nature reference, and a gardening marketplace.
The HortiPlex database: Contains plant images and data on Hawaiian plants, as well as links to other information sources
Dave's Garden, FL: Numerous tropical garden plant and great flower photos
TopTropicals, FL: Tropical plants for home and garden; great photos and concise descriptions
Gernot Katzer's Spice Pages: A compendium of spices and their use from around the world, plus great photos and detailed culinary and botanical descriptions
Trade Winds Fruit, CA: Huge database of tropical fruit and ornamental plants with brief descriptions and great photos
FloridaGardener.com: Lots of information regarding gardening in Florida, and how to care for your Florida plants, with brief descriptions and plant facts
Pine Island Nursery, FL: Primarily tropical fruit tree info; great images with concise descriptions; the Mango Variety Viewer is particularly interesting for the wealth of cultivars and detailed information
Danida Forest Seed Center, Denmark: Excellent info on seed handling and tree descriptions for the professional, with good photos
Daley's Fruit Tree Nursery, Australia: Tropical fruit tree data - great photos and descriptions

Birds
3-Rivers Eco-Lodge: A Dominica eco-tourism hotel website with a profusion of local bird calls.
Mangoverde World Bird Guide: With photos, calls and videos of numerous Caribbean birds
The Internet Bird Collection: A video feature of the Handbook of the Birds of the World with numerous West Indian birds
Patuxent Bird Identification Infocenter, MD. A USGS site with brief but comprehensive descriptions, photos and some calls of most N.American and Caribbean birds.
Sea Birds of Dominica - A very informative powerpoint presentation for sea birds boat trip; great photography.